Grunt: The Curious Science of Humans at War

1. SECOND SKIN What to Wear to War

AN ARMY CHAPLAIN IS a man of the cloth, but which cloth? If he’s traveling with a field artillery unit, he is a man of moderately flame-resistant, insect-repellent rayon-nylon with 25 percent Kevlar for added durability. Inside a tank, he’s a man of Nomex—highly flame-resistant but too expensive for everyday wear. In the relative safety of a large base, the chaplain is a man of 50/50 nylon-cotton—the cloth of the basic Army Combat Uniform, as well as the camouflage-print vestments that hang in the chaplain’s office here at Natick Labs.

The full and formal title of the complex of labs known casually as “Natick” is US Army Natick Soldier Research, Development and Engineering Center. Everything a soldier wears, eats, sleeps on, or lives in is developed or at least tested here. That has included, over the years and through the various incarnations of this place: self-heating parkas, freeze-dried coffee, Gore-Tex, Kevlar, permethrin, concealable body armor, synthetic goose down, recombinant spider silk, restructured steaks, radappertized ham, and an emergency ration chocolate bar with a dash of kerosene to prevent ad libitum snacking. Natick chaplains, for their part, have devised portable confessionals, containerized chapels, and extended shelf life[3] communion wafers.

It’s a balmy 68 degrees at Natick this afternoon. It may, at the same time, be 70 below zero with horizontally blown snow or 110 in the shade, depending on what’s being tested over in the Doriot. The Doriot Climatic Chambers were the centerpiece of the complex when it opened in 1954. Never again would troops be sent to the Aleutian Islands with seeping, uninsulated boots or to equatorial jungles with no mildew-proofing on their tents. Soldiers fight on their stomachs, but also on their toes and fingers and a decent night’s sleep.

These days, the snow and rain machines are rented out to L.L. Bean or Cabela’s as often as they’re used to test military outerwear. Repelling the elements is the least of what the US Army needs its uniforms to do. If possible, the army would like to dress its men and women in uniforms that protect them against all that modern warfare has to throw at them: flames, explosives, bullets, lasers, bomb-blasted dirt, blister agents, anthrax, sand fleas. They would like these same uniforms to keep soldiers cool and dry in extreme heat, to stand up to the ruthless rigors of the Army field laundry, to feel good against the skin, to look smart, and to come in under budget. It might be easier to resolve the conflicts in the Middle East.

LET US begin at Building 110, which is what everyone calls it. Officially it was christened the Ouellette[4] Thermal Test Facility, lending a flirtatious French flair to lethal explosions and disfiguring burns. The head textile technologist is a slim, classy, fiftyish woman of fine-grained good looks, dressed today in a cream-colored cable-knit wool tunic. I took her to be the Ouellette, and then she opened her mouth to speak and a hammered-flat Boston accent flew out and slammed into my ear. She is an Auerbach, Margaret Auerbach, but around 110 she’s just Peggy, or “flame goddess.”

When someone in industry thinks they’ve built a better flame-resistant fabric, a sample comes to Auerbach for testing. Some people submit swatches; others optimistically ship off whole bolts. Their hopes may be undone by a single strand of thread. “To see what our guys might be inhaling,” Auerbach heats a few centimeters of thread to around 1500 degrees Fahrenheit. The fumes produced by this are identified by gas chromatography. Flame-resistant textiles—some, anyway—work via heat-released chemicals. Auerbach needs to be sure the chemicals aren’t more dangerous than the flames themselves.

Once it’s established that the textile is nontoxic, Auerbach sets about testing its flame-stopping mettle. This is done in part with a Big Scary Laser (as the sticker on its side reads). Auerbach places a swatch in the laser’s sights. And here is the best part: To activate this laser, you push a giant red button. The beam is calibrated to deliver a scaled-down burst of energy representative of an insurgent’s bomb—a teacup IED. A sensor behind the swatch measures the heat passing through, yielding a figure for how much protection the fabric provides and what degree burn would result.

Auerbach switches on a vacuum pump that sucks the swatch tight against the sensor. This is done to approximate an explosion’s pressure wave—the dense pileup of accelerated air that can knock a person flat. More subtly, it forces clothing flush against the skin, which can heighten the heat transfer and worsen the burn. One of the winning attributes of Defender M, the textile of the current Flame Resistant Army Combat Uniform, or FR ACU (“the guys call it ‘frack you’”), is that it balloons away from the body as it burns.

The downside to Defender M has been that it tears easily. (They’re working on this.) The same thing that keeps it comfortable in hot weather also makes it weaker; it’s mostly rayon, which draws moisture but has low “wet strength.” If a garment tears open in the chaos of an explosion, now the protective thermal barrier is gone. Now you’re toast. The manufacturer throws a little Kevlar in, but it still isn’t as strong as Nomex, a fiber often used for firefighter uniforms. Nomex also has superior flame resistance: It buys you at least five seconds before your clothes ignite.

Auerbach explains that this is especially important for crews inside tanks and aircraft. “Where they can’t roll, drop, and…” She rewinds. “Drop, stop… what is it?”

“Stop, drop, and roll?”

“Thank you.”

Why not make all army uniforms out of Nomex? Poor moisture management. Not the best choice for troops running around sweating in the Middle East. And Nomex is expensive. And difficult to print with camouflage.

This is how it goes with protective textiles: Everything is a trade-off. Everything is a problem. Even the color. Darker colors reflect less heat; they absorb and transfer more of it to the skin. Auerbach goes across the lab to get a swatch of camouflage print cloth. She points to a black area. “You can see this has a pucker where it was absorbing more heat.”

“It has a what?” I heard her, but I need to hear her say pucka again. The fabulous Boston accent.

I would have guessed the military to be a fan of polyester: strong, cheap, doesn’t ignite. The problem is that it melts and, like wax and other melted items, it drips and sticks to nearby surfaces, thereby prolonging the contact time and worsening the burn. What you really don’t want to be wearing inside a burning army tank is polyester tights.[5]

To determine what degree of injury the heat would produce, Auerbach runs the reading from the sensor behind the cloth through a burn prediction model—in this case, one developed after World War II by original flame goddess Alice Stoll. Stoll did burn research for the Navy. To work out first- and second-degree burn models, she gamely volunteered the skin of her own forearm. You may excuse her for letting someone else help out with the third-degree burn curve. Anesthetized animals were recruited for this—rats, mostly, and pigs. Pig skin reflects and absorbs heat in a manner more like our own than that of any other commonly available animal. The pig as a species deserves a Purple Heart, or maybe Pink.

What Stoll learned: When flesh reaches 111 degrees Fahrenheit, it starts to burn. The Stoll burn prediction model is a sort of mathematical meat thermometer. The heat of the meat and how deeply into the skin that heat penetrates are the critical factors that determine the degree of the burn. A brief exposure to flame or high heat cooks, if anything, just the outer layer, creating a first-degree burn or, to continue our culinary analogy, lightly seared ahi tuna. A longer exposure to the same heat cooks the inner layers, too. Now you have a second- or third-degree burn, or a medium-rare steak.

Even without a flame, clothing can catch fire. The auto-ignition temperature for cotton, for instance, is around 700 degrees Fahrenheit. Exposure time is key. The heat pulse from a nuclear blast is extremely hot, but it’s traveling at the speed of light. Might it pass too quickly to ignite a man’s uniform? Natick’s early precursor, Quartermaster Research and Development, actually looked into this.

Operation Upshot-Knothole was a series of eleven experimental nuclear detonations at the Nevada Proving Grounds in the 1950s. The Upshot-Knothole scientists were mainly interested in the blastworthiness of building materials and tanks and bomb shelters, but they agreed to let the uniform guys truck over some pigs. Anesthetized Chester White swine, 111 in total, were outfitted in specially designed animal “ensembles” sewn from different fabric combinations—some flame-resistant and some not—and secured at increasing intervals from the blast.

Flame-resistant cool-weather uniforms with a layer of wool outperformed a series of thinner flame-resistant hot-weather uniforms—whose developers had surely, by “hot weather,” not had in mind the extreme swelter of nuclear blast. The researchers marveled to note “a complete lack of any qualitative evidence of thermal injury to the fabric-protected skin of animals dead on recovery at the [1,850-foot] station.” I don’t wish to be an upshot-knothole, but who worries about burns on subjects close enough to a nuclear explosion that they are, as the report succinctly terms it, “blown apart”? Despite the clanging absurdity of the scenario, it was a memorable demonstration of the importance of exposure time. With the fast-traveling heat from a bomb—including a more survivable one like an IED—a few seconds of flame resistance can make all the difference.

The wool helped, too, because hair is naturally flame-resistant. Natick has, of late, been looking into a return to natural fibers like silk and wool. Not only is wool flame-resistant and nonmelting, it wicks moisture away from the body. Auerbach says she has seen some very nice, soft, flame-resistant cool-weather sheep’s wool underwear. The hairs have to be descaled so the wool isn’t itchy, and the garments need to be treated to keep them from shrinking, and both these processes add to the cost. As does the Berry Amendment, which gives preference to domestic suppliers of military gear. The Berry is additionally problematic in this case in that—despite the breathless, eager assurances of the American Sheep Farmer’s Industry—there may not be enough sheep in all of America to fill the bill.

So let’s say your new textile is comfortable and affordable. The flame resistance plays well with the insect-repellent treatment and the antimicrobial stink-proofing. Now what? Now you bring some over to the Textile Performance Testing Facility. You run it through the Nu-Martindale Abrasion and Pilling Tester to get a feel for how quickly the treatments will succumb to soldierly abuse. You subject it to a couple dozen wash and dry cycles. Laundering removes not only grime but also, bit by bit, the chemicals with which a cloth or fiber has been treated. When I visited the textile testing facility, a man named Steve was waiting for some pants to get through an accelerated wash. One wash in the Launder-Ometer equals five normal washes, he told me.

“That’s something,” I said.

“Yup.” He stuck out his lower lip in a contemplative way. “Steel balls bang against the fabric.”

If only the minds of Natick could invent a fabric that didn’t need laundering. If everything splashed, smeared, or spilled on a uniform just beaded up and rolled off, if uniforms could be cleaned with a quick spray of water, think how much longer they’d last. And how much safer they’d be in the event chemical weapons rained down on them.

The minds of Natick are on it. Over in the liquid repellency evaluation lab, they’re putting to the test a new “super-shedding” fabric treatment technology. Escorting me to a demo will be Natick’s calm, likable public affairs officer, David Accetta. We meet up in his office, one side of which is piled with boxes from a recent move. A wall calendar features dog breeds. September is a large white poodle. Accetta was most recently deployed to Bagram Airfield in Afghanistan, where he spent his days writing press releases about the Army’s humanitarian efforts. His superiors would ask him why the stories rarely got any play. “They didn’t get it. It’s not news.” He relates this with no trace of anger. There are many irritating things about Accetta’s job, but he never sounds irritated. He takes everything in stride, which is a bad cliché to use for him, because he’s not a striding sort of guy. He’s more of a moseyer. He has long eyelashes and a slow way of blinking. I almost wrote doll-like there, but the adjective seems out of place with the rest of Accetta’s face, which is crossed by a thin, rakish scar that begins at one temple and curves down and around his cheek. I don’t ask about it, preferring to supply my own made-up narrative of flashing sabers and staircase choreography.

We are early, so we take a walk along Lake Cochituate, which forms a property line for part of the Natick grounds. Sunlight is scattered on a low chop. Water from the lake, a deep blue-green in today’s light, was at one time used to make Black Label lager. Natick activities pretty much put a stop to that. For a Superfund site, the grounds are quite pretty, with gazebos and meandering footpaths. Cylindrical gray-white Canada goose droppings add to the parklike atmosphere. It took a while to realize what these were, because I didn’t see any geese. It’s fall. Maybe they just flew south.

Accetta and I stop to watch an officer addressing a group of HRVs: human research volunteers—arms and feet and heads to go inside the parkas and boots and helmets. They are soldiers deployed to taste rations, sleep in new sleeping bags: test, report back, test something else. A temporary duty assignment at Natick is not necessarily a soft gig. I saw a photograph, from the sixties, of a group of soldiers in raincoats and waterproof pants, heads bent, hoods dripping, walking in circles under a simulated downpour. Apparently this went on for hours.

The volunteers, ten or so, stand in a row in the parking lot outside their barracks. A car backs out of a parking slot behind them. The soldiers take three steps forward, in formation, and one step up, onto the curb. When the car pulls away, they step backward and down. Anytime they walk someplace in a group of four or more, Accetta says, they have to be in formation. Like geese flying south.

THE DEMONSTRATION begins with the farting sound of a squeezable mustard bottle. A line of glistening yellow joins the duns and drab olives of a square of camouflage fabric. The cloth is clipped to a sloping board to foster roll-off. This being a roll-off test. As a cameraman and a small crowd look on, the line of mustard creeps down the cloth, holding its shape perfectly. A young chemical engineer, Natalie Pomerantz, directs onlookers’ attention to the terrain across which the condiment has just traveled. “No residue trail!”

Ketchup follows, then coffee, and milk, as though the owner of the uniform had engaged the enemy in a food fight. Everything rinses clean with water. Natalie invites me to feel the underside of the cloth, and I do. It is completely dry.

Natalie started with the easy ones. Liquids that are mostly water have high surface tension. That means that the molecules prefer to bond more strongly to each other than to most of the things you might spill them on. A liquid with lower surface tension, like alcohol, won’t bead up on a fabric the way water will; it soaks right in. A bead of water is a molecular huddle, a withdrawal inward, a refusal to join hands with strangers. Confronted with air, the surface of water pulls together powerfully enough to form a weak skin. The insect kingdom has water striders, but no gin striders. At the far high end of the surface-tension spectrum is mercury. Mercury beads up and rolls off pretty much any surface you drop it on without leaving a trace.[6] One of mercury’s qualifications for old-timey thermometerdom—along with staying liquid in extremes of cold and heat—is that it doesn’t wet the inside of the glass. No residue trail! So you can clearly read the temperature.

Many of the things the military tends to spurt and dribble on itself—motor oil, aviation fuel, hexane—have far lower surface tension than water. Natalie drips motor oil on another square of cloth. She picks up a cup of water and launches the contents like an outraged dinner date. Again, the mess rinses away with no trace remaining. “That was the money shot,” a colleague says.

Natalie is nodding. Beaming, even. “This is like a day out in the sun for us.” She’s joking, but it’s true in a way, in a good way. The delight she takes from science is an effervescence, something sparkly and hard to hold back. We should all love our jobs this much.

The super-repellent coating takes its inspiration from the leaves of the water lily. The surface of a lily pad, viewed under an electron microscope, is a carpet of tiny nubs, each covered with yet-smaller nano-nubs of waxlike crystals. (Paraffin wax is itself an effective fabric waterproofer, but it’s too flammable for the military to use.) The tiny nubs and peaks reduce the contact and interaction between the cloth and whatever liquid spills on it. The coating also makes the surface more energetically stable, further discouraging interactions between the textile and the glop.

Though the publicity for this “super-shedding” coating has focused on its grime-shunning properties—“self-cleaning underwear” is how Accetta reeled me in—the more important application is protection from chemical and biological weapons. The first garments to feature the new technology will be an outer shell and pants: a chem/bio suit. Garments like this include a layer of activated carbon (also known as activated charcoal) to bind up noxious organic materials. The super-repellency means this layer can be thinner; if 95 percent of what hits a garment rolls right off it, that means far fewer activated carbon receptor sites are needed to bind up the poisons. That’s good, because a garment with a thick layer of activated carbon is hot and uncomfortable. It’s like wearing an air filter. With protective clothing, comfort is paramount. If it’s uncomfortable, troops will be tempted to flout safety regulations and stuff it under their seat.

Likewise if they hate how it makes them look. “With protective gear especially, it’s key that you design something that’s kind of sleek and cool, because otherwise they’re not going to want to wear it.” That is a quote from Annette LaFleur, the US Army’s top staff fashion designer and the next line item on “MARY ROACH SCHEDULE as of 1400 hrs 20 September 2013.”

A ZIPPER IS a problem for a sniper. Here is a man who may spend an entire afternoon on his belly, sliding around on rubble and earth. If his top closes with a zipper, sand and muck will be ground into the spaces between the teeth, and soon it will jam. A zipper is, furthermore, uncomfortable to lie on. As are buttons. A “hook-and-loop fastener” like Velcro is a less protuberant front-closure option, but it’s noisy. I have heard stories of Special Operations guys whose Velcro put them in danger by revealing their position. A stealthier model is on Natick’s hook-and-loop fastener agenda.[7]

The designer of the new sniper base suit—Annette LaFleur, as pretty as the name suggests—is showing us how she got around this by making the top a side-closure garment. She indicates a dress form, standing in one of the work bays in Natick’s Design, Pattern, and Prototype Facility. The headless dress form, a staple of the fashion industry, takes on an uncomfortable poignancy when the garment under construction is designed for war. Our sniper looks like someone else’s sniper got him first.

LaFleur takes the fabric between her fingers. “This is a coated Cordura we went to.” The bolts of fabric may be olive drab and the sewing machines built for Kevlar, but this is still a design studio, and LaFleur’s language reflects this. (She described flame-resistant uniforms as one of the “things that are hot right now.”) However, LaFleur didn’t go to Cordura because it’s in style. She chose it because it’s durable and flame-resistant, and because the coated backing keeps moisture from seeping through. And that’s important if you’re lying someplace damp waiting to kill someone. Even the sleek, uncluttered lines of the sniper top are functional, a result of the side closure and of an earlier decision to move the pockets from the front to the sleeves for easier access. (The ensemble will stop looking sleek should elements of the accessory kit be added. Snipers can customize the back, pants, and helmet by tying in, say, jute strands to blend in with brush or grassy terrain. LaFleur, but probably not many snipers, compares this to macramé.)

LaFleur points to a cloth flap called a button placket, which covers the buttons so they don’t get chipped. She needn’t have worried. US military specifications for buttons include a minimum compressive strength, tested by placing the item between flat blocks of steel and bearing down until “the first audible sound of cracking.” Federal button inspectors display a medieval zeal for their work. Other inspection methods include pressing a hot iron to the button’s back, boiling it in water, and pulling the shank until it separates from the body.

US government button specifications run to twenty-two pages. This fact on its own yields a sense of what it is like to design garments for the Army. Although the Army requires its clothing designers to have a fashion design degree, fashion—in the sense of individuality expressed through appearance—is the opposite of an Army requirement. It’s a violation of policy. US Army Appearance and Grooming Policies prohibit anything to which the adjectives “extreme, eccentric or faddish” might apply. The United States Army does not abide: unbalanced or lopsided hairstyles, “barrettes with butterflies,” “large, lacy scrunchies,” teased hair that rises more than 3½ inches from the scalp, hair that is dyed green, purple, blue, or “bright (fire-engine) red,” Mohawks, dreadlocks, slanted or curved parts, flared sideburns, tapered sideburns, individual sideburn hairs that exceed 1/8 of an inch when fully extended, goatees, beards of any kind, Fu Manchus, and mustaches that cover any part of the upper lip or “extend sideways beyond a vertical line drawn upward from the corners of the mouth.”[8]

The driving aesthetic of military style is uniformity. Whence the word uniform. From first inspection to Arlington National Cemetery, soldiers look like those around them: same hat, same boots, identical white grave marker. They are discouraged from looking unique, because that would encourage them to feel unique, to feel like an individual. The problem with individuals is that they think for themselves and of themselves, rather than for and of their unit. They’re the lone goldfish on the old Pepperidge Farm bags, swimming the other way. They’re a problem.

“You’re more of an engineer than a designer,” says LaFleur of her work. She got her start designing swimwear. It is a more logical transition than it might at first seem. A bathing suit requires expertise with high-performance active-wear fabrics and an understanding of the specialized activity they’re needed for. Ditto, say, a concealable body armor vest. LaFleur’s colleague Dalila Fernandez came to Natick from the now-defunct Priscilla of Boston, purveyors of high-end wedding dresses. Same thing here: A wedding gown entails multilayering of expensive specialty fabrics for an outfit whose useful lifespan may come and go in a single afternoon. Much like a bomb suit. Form follows function—although admittedly more so here than in most studios. Only a military clothing designer’s portfolio would include a mitten that accommodates a lone forefinger in firing position.[9]

In an Army gone increasingly high-tech, the modern military uniform is less an outfit than a system. It’s a holder of gizmos and gear and the ammunition and batteries that go in that gear. Back before hulking body armor and gear-festooned vests supplied the intimidating profile, the clothing itself was sometimes recruited for the task. High hats and epaulettes made officers appear taller and more broad-shouldered. And the boots. The boots. Dashing knee-high leather boots protected the pant legs, yes, but surely they also boosted morale. Uniforms created not just uniformity but brio and self-confidence. They were crisp, flattering, finished with piping and grosgrain and tassels. They were, to quote Annette LaFleur, “very couture.”

The current combat uniform, with its sensible emphasis on hot-weather comfort, is worn loose and untucked. It doesn’t say “ready to kill” so much as it says “ready for bed.” Still, clothing remains an important Army morale issue. The ACU used to be unisex, but women complained. The shoulders and waist were too wide for many women, or the hips too narrow. The knee patches tended to hit at the shins. Women hated it. They hated it enough that the Army commissioned a female uniform.

“But you can’t call it that,” Accetta says. “Because some of the guys are wearing them.” It’s called the Army Combat Uniform–Alternate, a uniform “for smaller stature Soldiers.”

Every now and again, military fashion has evolved not out of practicality or research or matters of morale but simply out of the sartorial inclinations of one high-ranking individual. British history holds a General Cardigan and a General Raglan, and I like to picture them in their tented quarters, sketching outerwear by lantern light. Most recently, an Army chief of staff decided that black wool berets would be the headpiece of the Army Combat Uniform, not so much because wool is flame-resistant and moisture-wicking but because he dug the look. He dug it despite having to wrangle an exception to the Berry Amendment. He dug it despite his troops’ near-universal preference for visored cloth caps. And despite their having every good reason to prefer caps, because not only do caps shade the eyes but they’re cooler than berets, and lighter and less bulky in a pants leg pocket. (It took ten years, but the Army has finally got its caps back on.)

The most talked about—around Natick—example of sartorial rank-pulling was the Universal Camouflage Pattern used on the Army Combat Uniform beginning in 2005. The idea had been to develop a single camo pattern that would provide concealment for troops in desert, urban, and woodsy settings. The Natick Camouflage Evaluation Facility came up with thirteen pattern and color combinations, duly sent overseas for field tests and feedback. Before the data was in and the study completed, a highly placed general went ahead and picked a pattern. It was not even one of the ones being tested. The new camouflage performed so poorly in Afghanistan that in 2009, the Army spent $3.4 million developing a new and safer pattern for troops deployed there.

Camouflage is interesting from a fashion perspective. As a rule, the military starts—rather than follows—fashion trends in the civilian sphere. Every now and then, they start them and then follow them. Midway through the previous century, Army camouflage prints began showing up in mainstream fashion. It began with clothing and took off from there. As I write this, you can get on the internet and order camouflage wedding bands, dog sweaters, onesies, condoms, flip-flops, hard hats, and football cleats. Camo print became so popular that eventually Navy personnel began clamoring for it. To the embarrassment of many, the current Navy working uniform is a blue camouflage print. Unsure whether perhaps I was missing the point, I asked a Navy commander about the rationale. He looked down at his trousers and sighed. “That’s so no one can see you if you fall overboard.”

No military fashion foolery can compete with the saga of the orange-red underwear. Around the turn of the last century there was, in the phrasing of a paper in the June 1897 issue of Medical Bulletin, “a very prevalent idea that red underwear possesses some occult medical value.” Baseless as it was, the notion made its way to the office of the US surgeon general. A Lieutenant Colonel William Wood reported that British Army officers in India had found some relief from the intense tropical sun by lining their hats with red cloth. A study was commissioned, using troops stationed in the Philippines as subjects. Though a small number of caps were prepared, the Americans seized on the idea of red underwear—perhaps as a sort of secret asset, a hidden psychological edge, like fabulous lingerie or lifts in one’s shoes. Five thousand pairs of orange-red drawers and undershirts were shipped from a War Department depot in Philadelphia, along with a like number of white drawers, as controls. Mental and bodily vigor to be monitored for one year. One thousand men conscripted as subjects.

The garments arrived on the first of December 1908. Whereupon the setbacks began. Four-fifths of the underwear was too tight for all but the smallest men. Perhaps, having seen the destination of the shipment, the clothiers had misunderstood and fashioned the items for the slighter, trimmer bottoms of the Filipino male. Perhaps they were cutting corners. Who can say. Six hundred men were dropped from the study. Worse, the underpants had been sewn from heavy dungaree cotton, causing the men to perspire in places where no one wants to perspire, surely counteracting any mystical cooling properties that the color might have conferred. The sweating proved doubly vexing, as the dye ran badly. Much joshing and ridicule—“bantering by their companions”—ensued. Over a month of washings, the red underwear progressed to yellow and onward to a “dirty cream color.” The cap liners, though less frequently laundered, ran in the rain or when the men sweated, causing red blotches and rivulets running down their faces and yet more bantering.

At the end of a year, the men were interviewed about their experience with the special underwear. Only 16 of 400 had anything positive to say. The red underwear was hotter and scratchier. It “outraged the sensibilities of the wearer.” In addition to prickly heat and rashes and a higher rate of heat exhaustion, it was blamed for headaches, dizziness, fever, blurred vision, boils, and colic. “An Experiment with Orange-Red Underwear” was read aloud at a biennial meeting of the Far Eastern Association of Tropical Medicine, no doubt jollifying the usual assortment of malaria and foot fungus reports.

While we are on the topic of hot, uncomfortable military intimates, a word about Kevlar underwear. A version of which was successfully marketed to the British Army: Blast Boxers[10]—protection against life-altering injuries.

“There was some controversy over this,” Accetta says.

LaFleur’s large, beautiful eyes widen. “She’s recording you.”

“Which I started.”

Fox News had called, asking why the Brits had bombproof underpants and our guys didn’t. “No such thing,” Accetta told the reporter. He said they were working on something else, and then he got off the call and dialed the Natick ballistic protection guys. What in fact were they working on? Silk underwear, said the ballistics guys. No, really, they said. Unlike other naturally breathable textiles—cotton, say—silk doesn’t fragment and riddle a wound with bits of fiber that can seed infection. It’s surprisingly strong. Spider silk, specifically, has a better strength-to-density ratio than steel. (Natick at one time had a “spider room” in the basement of Building 4 and a team of scientists working to parse the unique protein structure of spider webbing in order to synthesize it.)

Despite its strength, silk doesn’t inspire confidence. Kevlar does that. People don’t realize that a khaki-weight Kevlar (or its newer cousins Spectra and Dyneema) doesn’t stop bits of metal packed into improvised explosives. For that you’d need fifteen to forty plies—far too heavy for underwear. What Blast Boxers stop is dirt and sand launched by buried bombs. That is important, because dirt carries fungi and bacteria that can cause deep-lying, hard-to-conquer infections in a wound. Blast Boxers are excellent. But they are most assuredly not, as the advertising material implied, bombproof. “Honestly,” Accetta says, “if the insurgents can make a bomb big enough to blow up a seventy-ton M1 tank, they can certainly make a bomb that’s going to blow up your underwear.”