The most useful artillery for US troops in Afghanistan is reported to be the HIMARS rocket launcher system:
HIMARS carriers only one six MLRS rocket container (instead of two in the original MLRS vehicle), but the 12 ton truck can fit into a C-130 transport (unlike the 22 ton tracked MLRS) and is much cheaper to operate. The first HIMARS entered service in 2005, about a year after GPS guided rockets did.
The 680 pound GMLRS (guided multiple launch rocket system) missile is as GPS guided 227mm rocket that entered service six years ago. It was designed to have a range of 70 kilometers and the ability to land within meters of its intended target, at any range. This is possible because it uses GPS (plus a back up inertial guidance system) to find its target. Two years ago, the army tested GMLRS at max range (about 85 kilometers) and found that it worked fine. This enables one HIMARS vehicle to provide support over a frontage of 170 kilometers, or, in places like Afghanistan, where the fighting can be anywhere, an area of over 20,000 square kilometers. This is a huge footprint for a single weapon (an individual HIMARS vehicle), and fundamentally changes the way you deploy artillery in combat.
HIMARS: High Mobility Artillery Rocket System
