In Iraq, the The U.S. Army and Marines both found that more frequent and aggressive use of snipers made for more successful combat operations. Each army brigade now has about three dozen trained snipers, and most brigades have encouraged the selection and training of more snipers within infantry companies. The ability to take down enemy troops with single shots is a major combat advantage, but can only be done if you have better trained troops and much better reconnaissance and observation on the battlefield. 

The army has a five week sniper school, and the marines have a ten week course that is considered one of the best in the world. These schools turn out professional snipers who know how to operate independently in two man teams. Marine regiments (about the same size as army brigades) have about three times as many snipers per battalion as do army units. But both the army and the marines are taking advantage of the greater number of veteran troops in their combat units, and the fact that just about every soldier has a rifle with a scope, and has a lot of target practice behind them. Infantry commanders are encouraged to find and designate about ten percent of their men as sharpshooters (sort of sniper lite) and make use of these guys to take out enemy troops at a distance, and with single shots. This is a trend that has been growing for over a decade, but has now become a major feature of American infantry tactics. 

The marines wont release any numbers of sniper kills (except that the top scoring sniper in Fallujah had 24 kills as of late April), but it is known from emails coming back that the marines use snipers, and sniping tactics (for non-snipers), extensively. Part of this is to comply with the Rules of Engagement (ROE) that call for minimizing civilian casualties. Most often, the marines only use a lot of fire power when they are ambushed (there is no better way to deal with an ambush than to blast your way out of it). But most of the Iraqi gunmen are killed by single shots, usually by the trained snipers, after the snipers and their commanders had carefully set up sniper firing positions that covered areas they knew Iraqis liked to travel through. UAVs and lots of scouting, plus questioning of prisoners, reveals the Iraqi routes and makes them deadly to use. This has terrorized the Iraqis, which is exactly what it is intended to do. The army and marine snipers particularly like to work at night, when their night vision and thermal imaging equipment enables them to shoot accurately in the darkness. This further reduces the chance of civilian losses, and increases the terror.

The men who go through the sniper school receive lots of training on how to choose a good shooting position, get to it unseen and remain unseen for as long at is takes to get the shot, or shots, available. These professional snipers also learn to use larger caliber 7.62mm and 12.7mm (.50 caliber) sniper rifles. These are single shot weapons that are designed and built for accuracy at very long ranges (over a thousand meters for the 12.7mm rifle.) The sharpshooters are mainly excellent shots at shorter ranges, and have whatever training they can pick up on how to find the best shooting position. Army and marine officers have learned how to use snipers more frequently in the past two decades. Instead of regarding the snipers as just a specialized weapon, for special occasions, combat unit commanders now see snipers as a standard type of trooper, to be used immediately in any combat situation, just as they would mix and match riflemen, machinegunners, grenadiers (with 40mm grenade launchers) and other weapons available to infantry companies and battalions. 

The emphasis on greater accuracy in the use of weapons now applies to all weapons. Better trained troops can carry out complex battlefield maneuvers automatically, even when (especially when) under fire. While some of the anti-government gunmen in Iraq have demonstrated evidence of some military training, it has proved far inferior to that of the American troops they face. In combat, the side that is better trained wins, and takes fewer casualties doing so.