Although coalition casualties are declining in Iraq, American troops are acutely aware of the danger they face every day from ambushes and bombs. The main form of protection is carefully thought out tactics for moving around, and training that teaches troops how to spot an ambush or bomb, and how to react if attacked. But there are also protective devices, the principal ones being the protective vest with SAPI (Small arms protection inserts) plates. SAPI are slipped into pockets in the front and back of protective vests (flack jackets) and provide protection from rifle bullets. So far, SAPI has saved the lives of at least 29 soldiers in Afghanistan, and well over a hundred in Iraq (official stats won't be available until March.) There are basically two types of plates used by the troops. The basic "Level 3" plates are 10x12 inches, weigh 4.6 pounds each and cost about $450. A lighter weight (3.3 pounds) plate costs $750. Level 4 plates, weighing about 6.4 pounds each, can stop armor piercing bullets. SAPI are made of boron carbide ceramic with a spectra shield backing. This combination causes bullets to fragment and slow down before getting through the plate. Occasionally, some fragments will get through, but these are stopped by the layers of Kevlar that make up the flak jackets. The success of the plates, and the frequent attacks on U.S. troops in Iraq has led the U.S. Army to try and get enough plates for all troops in the combat zone, not just those in infantry units. This is more of a morale issue than anything else, as non-infantry troops are most frequently exposed to bombs and RPGs. The fragments from these weapons can be stopped by the flack jackets without the plates. But morale is important, so the army is trying to get enough SAPI plates for everyone. Late last year, production of SAPI plates was increased from 3,000 a month to about 25,000 a month. 

More importantly, at least for non-combat troops, orders for the heavily armored M1114 model of the hummer was been increased from 235 to 2,957. The M1114 has 3,000 pounds of Kevlar, ceramic and metal armor added to provide protection from bullets, bomb fragments and anti-personnel mines. This doubles the cost of the vehicle, to about $150,000. Troops have been adding armor, sandbags and other material to their vehicles. But this has a downside, as these improvisations often don't add much protection, and sometimes make the vehicles unbalanced and more prone to accidents (which have injured more Americans than hostile action.) The Department of Defense has given the army $130 million to buy add-on armor and Kevlar blankets to mount on trucks used in Iraq.

While SAPI and armored vehicles get most of the credit for protecting the troops, what makes the most difference is the police operations to round up the attackers, and the ability of the troops to avoid attacks, and effectively defend themselves when they are hit.