BAGHDADI, Iraq -- Roadside bombs have killed or wounded almost 20,000 American troops in Iraq since the war began, a tragic cost that continues despite a two-year, $8 billion Pentagon campaign against networks of bomb-makers and those who plant and detonate the devices.
Crafted out of still-plentiful weapons looted from Iraqi arms depots left unguarded after the 2003 U.S. invasion, the bombs are a deadly form of warfare that U.S. officials acknowledge will continue to kill and maim Americans wherever they deploy, long after the Iraq war is over.
"This is a long-term problem, and it is not peculiar to Iraq and Afghanistan," said retired Army Gen. Montgomery Meigs, who directs the Pentagon's campaign to counter the bombs, known as improvised explosive devices, or IEDs. "This is going to be a permanent aspect of our military and diplomatic life, regardless of [what happens in] Iraq and Afghanistan."
Eleven soldiers were killed by makeshift bombs in the past week, pushing the U.S. death toll in Iraq over 3,500, a grim reminder that in this war, America's military power and technological prowess have in some measure been thwarted.
Deaths from IEDs have risen from 25 in May 2004 to 88 last month, the highest monthly toll since the war began. Nearly 1,400 Americans have been killed by the bombs since the start of the war in March 2003.
Accounting for the wounded is slower. According to the Defense Department, 17,773 U.S. military personnel were wounded by bombs as of May 19. These casualties are joined by a growing number in Afghanistan, where roadside bombs have killed 84 U.S. troops and wounded 609, as of May 19.
The battle against IEDs is being waged by troops armed with better training and an array of new sensors and devices that can jam radio and other signals that detonate the bombs.
Overhead, swarms of manned and unmanned aircraft watch key roads and intersections to detect and track bomb-planters. Surveillance is kept from towers and tethered balloons as well. Sniper teams often kill anyone caught placing an IED, or they follow the bomb planters in an attempt to penetrate their organization.
Overall, troops are discovering half of the planted bombs before they explode, and Pentagon officials assert that insurgents must work six times harder to inflict one American casualty with an IED.
Yet officials and troop commanders here acknowledge that in this deadly struggle between attackers and defenders, the insurgents have the upper hand. That is why they expect IEDs to torment American troops wherever they deploy in the years ahead. The materials are cheap, the explosives are easy to mix, and the wiring diagrams are on the Internet. The bombs are extremely effective, causing particularly gruesome casualties that directly affect domestic support for the war and requiring a costly diversion of money and talent to building defenses.
Iraqi insurgents have access each year to $3 trillion in new communications technology from which they can adapt innovative ways to combine and detonate explosives, using codes transmitted by cell phones or garage door openers, for example, Meigs said in an interview.
In the struggle to develop and deploy defenses against this onslaught, he added, "we don't have $3 trillion."
Meigs, director of the Joint IED Defeat Organization within the Pentagon, received a budget of $3.5 billion last year and $4.5 billion this year. The money funds research, development and production of highly classified sensors and other electronics, and some of the IED training of troops.
Out here in Anbar province west of Baghdad, IEDs have been common killers, and soldiers and Marines tackle the problem with a kind of aggressive fatalism.
Midway through a recent patrol outside this Euphrates River town, a Marine sergeant spotted what appeared to be a freshly filled hole on the side of the road. He called a halt, Marines piled out of vehicles to provide security while one Marine whipped out a shovel and started digging. Three feet down, he concluded it was just a hole - not an IED.
Joseph Blei's experience was different. As he was at the wheel of an up-armored Humvee on a different security patrol, an IED detonated near his right front fender, blasting the hood, wheels and engine block into tangled wreckage, slamming turret gunner Jeremy Tinnel over onto his .50-caliber machine gun, and shoving the three-ton vehicle in a screeching skid through clouds of acrid smoke and debris.
"When we stopped sliding, everybody got out. That was pretty much it," shrugged Blei, a 19-year-old lance corporal from Philadelphia, a day after the incident. For Cpl. Daniel Smith, the third Marine in the Humvee, it was the second IED strike he had survived in three months.
The heavy armor added to most Humvees in Iraq undoubtedly saved their lives.
Most Humvees originally deployed in Iraq had no armor, and troops commonly rode around with the doors taken off. But the Pentagon had to scramble to add armor after insurgents began planting relatively primitive bombs, often anti-personnel or anti-tank mines dug into the pavement and detonated by a pressure plate or by wire.
But insurgents responded to the newly armored vehicles by building bigger bombs, often wiring together several mines or artillery shells, detonated by more sophisticated firing devices. In August 2005, they blew up a 37-ton amphibious tractor, killing 14 Marines. At least three 70-ton Abrams M1A2 tanks have been disabled by IEDs.
Now the Army and Marines are buying 11,400 heavier vehicles with V-shaped hulls to deflect the force of blasts from beneath the vehicles. Total cost: $8.4 billion.
But some experts believe these "MRAPs" or Mine Resistant Ambush-Protected vehicles, are still vulnerable to a direct shot from the side and that ultimately, no armor is a perfect defense.
"I'm a tanker, and I know there's nothing you can't blow a hole through," said Col. David Hain, chief of staff for ARCENT-Forward, the Army's Middle East headquarters.
And insurgents in Iraq and increasingly in Afghanistan are using armor-piercing IEDs to attack heavily armored vehicles. Many of these simple devices are about the size of a coffee can with a disk at one end. Upon detonation, the disk is forged into a molten steel slug that burns through steel armor and explodes inside the vehicle with hundreds of lethal droplets of burning metal.
"Every time you add armor to a vehicle, it's very easy for the enemy to adapt," Meigs said.
Along with better armor, troops are being given flameproof jumpsuits, quick-release seatbelts and training on how to get out of an overturned vehicle quickly. In their final weeks of training before deployment, troops are taught to recognize the telltale signs of roadside IEDs: the plastic bag with an odd shape, a thin copper wire spooling away from a pile of trash, fresh scuff marks in the dirt where an IED might be planted.
But the difficulties of finding and defending against IEDs convince most officials that the biggest payoff is attacking the insurgent networks that organize and finance IED operations. Meigs characterized these networks as "organized crime, corrupt secret intelligence guys and paramilitaries" integrated into social and tribal networks that have existed in secret in Iraq "for centuries." Different networks operate in Afghanistan and other places where they confront U.S. interests, he said.
"The ordinary military officer doesn't think in those terms; we are not trained to see" those kinds of criminal relationships, he said. He said traditional law enforcement and anti-organized crime techniques can help.
"But it is not a trivial problem," he said.