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The four hostages that Israeli forces rescued earlier this month in Gaza were found inside buildings. Some of the other hostages taken by Hamas last fall will be harder to find because they're probably held underground in miles of tunnels. That ancient tactic of going underground is still very much in use, so much so that the U.S. military has increased its focus on fighting in tunnels, one of the most dangerous forms of warfare. WUNC's Jay Price reports from Fort Liberty, N.C. And a warning, this story includes the sound of gunfire.
UNIDENTIFIED SOLDIER #1: Those two trucks, we're not seeing weapons in the back...
JAY PRICE, BYLINE: A special forces soldier on lookout feeds information to a nearby team entering a cinder block house.
UNIDENTIFIED SOLDIER #2: (Inaudible).
PRICE: It's a training exercise, so they're firing non-lethal rounds at role-playing terrorists. But their main target, a top leader, flees into a tunnel, hidden in a back room. They peer in, spot him and quickly start firing. Then they toss a flash bang, a grenade designed to disorient. U.S. geopolitical foes like China, Iran, North Korea and Russia have long been building tunnels and bunkers to shield their militaries. And in recent years, Hamas and other groups have followed suit.
So the U.S. military has responded, building tunnel warfare training facilities like this one at Fort Liberty. It's one of the Army's largest and most elaborate, nearly two-thirds of a mile of disorienting twists and turns, hatches and doorways. The man playing the role of the high-value target is a staff sergeant named Adrian. The Army allows special operations soldiers to be identified only by their first names. He said soldiers need a really good reason to enter tunnels, where they're usually at a disadvantage.
ADRIAN: You don't know. You have no idea how big the tunnel system is or how small it is, how compressed it is. Where's the obstacles? Is there trip wires? Is there false doors?
PRICE: Mike Murray oversees the sprawling base's dozens of training ranges. He helped plan the elaborate newer section of the tunnels, which was finished in 2020.
MIKE MURRAY: Want to try to make it as complicated as possible.
PRICE: Some tunnels open into spacious rooms that could be used for, say, a command center, medical treatment or storing arms. Others squeeze down until you're crawling.
MURRAY: Now you're on your hands and knees, complete darkness. Maybe your elbows are banging the side of the walls.
PRICE: There's good reason the U.S. and other nations are doing more of this kind of training, says Daphne Richemond-Barak, author of the book "Underground Warfare" and an assistant professor at Reichman University in Israel.
DAPHNE RICHEMOND-BARAK: For the last two decades, this tactic has indeed become more popular with non-state actors.
PRICE: For groups like Hamas, Hezbollah, ISIS, and al-Qaeda, that the U.S. and other nations designate as terrorists, going underground helps them blunt the technological and numerical advantages of the militaries hunting them.
RICHEMOND-BARAK: And it is spreading as a global threat from theater to theater, and we've witnessed tunnel warfare on virtually every single battlefield since 9/11.
PRICE: Underground warfare goes back to, well, cave dwellers, but these days, it can be startlingly sophisticated. North Korea has thousands of bunkers, tunnels and even air bases, complete with subterranean taxiways. For Americans, perhaps the best-known cases in recent history were in Vietnam, where the Viet Cong dug vast complexes. Scottish born John Keaveney was sent into them. He was one of the U.S. troops known as tunnel rats.
JOHN KEAVENEY: You learn to use your senses 'cause it's very dark. And so, you know, you learn to smell things and listen good.
PRICE: He crawled into tunnels more than 50 times. Waiting inside, he found booby traps, snakes, spiders and sometimes enemy fighters. The stress contributed to what he now knows was PTSD.
KEAVENEY: When I came home, I didn't know what was wrong with me. I thought I just spent too much time in the tunnels.
PRICE: Richemond-Barak, the professor, says those psychological effects are a key reason troops need to be trained for fighting underground.
RICHEMOND-BARAK: You lose your sense of space, your sense of direction, your sense of time very quickly inside the tunnel. And it's striking. The confinement and nature of this darkness really takes you by surprise.
PRICE: The U.S. military is also developing technology like robots that can explore and map tunnel systems, and communication devices that can work underground. But Richemond-Barak says there's no substitute for training exercises like the one at Fort Liberty, where troops can get used to how their minds and bodies react to one of the toughest forms of combat. For NPR News, I'm Jay Price at Fort Liberty, N.C. Transcript provided by NPR, Copyright NPR.
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