BAGHDAD — U.S. troops working the streets of the capital fear one Iraqi weapon more than others -- a copper-plated explosive that can penetrate armor and has proved devastating to Humvees and even capable of severely damaging tanks.
The power of what the military calls an EFP -- for explosively formed penetrator, or projectile -- to spray molten metal balls that punch through the armor on vehicles has some American troops rethinking their tactics. They are asking whether the U.S. should give up its reliance on making constant improvements to vehicle defenses.
Instead, these troops think, it is time to leave the armor behind -- and get out and walk.
"In our area, the biggest threat for us is EFPs. When you are in the vehicles, you are a big target," said Army Staff Sgt. Cavin Moskwa, 33, of Hawaii, who patrols Baghdad's Zafraniya neighborhood with the Bravo Battery of the 2nd Battalion, 17th Field Artillery Regiment. "But when you are dismounted ... you are a lot safer."
In the last three days, 15 U.S. troops have been killed in Iraq, nine of them in two powerful roadside bomb blasts. The military does not publicly identify the kind of weapon used in improvised explosive attacks, but the deadly nature of the blasts Wednesday and Thursday suggested that EFPs may have been used.
The deaths brought to 3,545 the total number of U.S. troops killed in the Iraq theater since the March 2003 American-led invasion, the U.S. military said. Hundreds of these troops have been killed by EFPs and other kinds of improvised explosive devices, or IEDs. The Pentagon's most recent Iraq status report said EFP attacks were at an all-time high.
Foot patrols, of course, are not a fail-safe method. On city streets, snipers remain a threat. And bombs can still kill dismounted troops. But when blasts occur in the middle of a foot patrol, the number of casualties are generally lower because the troops are more spread out.
Before a foot patrol last week through a neighborhood next to Baghdad's Sadr City district, a private with Alpha Company of the Army's 1st Battalion, 8th Cavalry Regiment, began complaining about having to walk. But EFPs have claimed the lives of several soldiers in the unit, and Sgt. Leland Kidd, 28, of Gonzales, Texas, said the private should be thankful they were on foot.
"When I walk on my feet, I don't have to worry about being blown up," Kidd told the private. "In the vehicle, I have to."
Top commanders have been encouraging more such units in Baghdad to take just that tack.
A counterinsurgency guidance memo released last week by Army Lt. Gen Raymond T. Odierno, the commander of day-to-day military operations, urges Iraqi and American troops to "get out and walk."
The memo argues that although Humvees offer protection, they also make units predictable and "insulate us from the Iraqi people we intend to secure."
The original draft of the memo, written by counterinsurgency expert David Kilcullen, goes further. It notes that EFP attacks on Humvees damage them heavily. "So we gain little in safety, but sacrifice much in effectiveness," the draft reads.
One reason for the increased number of troops victimized by roadside bombs is that there are more forces in Iraq now, Marine Gen. Peter Pace, chairman of the Joint Chiefs of Staff, said at a Pentagon news conference Thursday. This month, the final additional American combat units arrived in Baghdad, as part of a counterinsurgency strategy announced by President Bush in January that has increased the U.S. military presence in Iraq by 28,500 troops.
"As we're taking the fight to the enemy with the additional troops, we can expect that there's going to be tough fighting ahead," Pace said. "So it is an expectation that this surge is going to result in more contact and therefore more casualties."
But another reason for the rising death toll is the ability of Iraq's militants to adapt to new U.S. military tactics.
During the 2003 invasion, most American Humvees were outfitted with flimsy canvas doors. When the first improvised explosive devices made from artillery shells appeared, the military scrambled to put stronger armor on the vehicles. Since then, the military has repeatedly upgraded Humvee armor as militants have made bigger and bigger bombs.
But the small and easily hidden EFPs, which often are powered by C-4 plastic explosives, are not just a more powerful IED. Military personnel experienced with the projectiles say that what makes the weapons so deadly is that they use the Americans' own armor against them. As the hot copper slug melts through the armor of a Humvee, it transforms the protective plating into shrapnel that sprays into the passenger cabin, they say.
"We joked about going back to canvas doors. That way, unless it hits you directly, you are OK," said Army Sgt. William Bowman, 31, of Fort Myers, Fla.