The U.S. military has been testing a high-tech beam that can detonate improvised explosive devices, the most deadly weapon used against American forces in Iraq and Afghanistan. The Pentagon would not release full details of the technology, but announced that the beam could trigger IEDs being transported or built by insurgents. “This is an offensive capability that will change the face of the war,” said Marine General James Mattis. The weapon was used in Iraq in 2005 and 2008, but has yet to be employed in Afghanistan because of the rough terrain and its ungainly size (a “tractor trailer-size vehicle” is required to move it). IEDs are the top killer of U.S. soldiers in Afghanistan. According to the Pentagon, there were 3,736 IED attacks in 2009—more than double the number of attacks that occurred in 2008.