Soldier with a rifle-mounted M203 grenade launcher (as opposed to the M320)
The XM25 is the deadliest hand weapon in the army arsenal. Why? Because it can fire 25mm rounds that explode at any distance set by the soldier, killing people protected behind walls or trenches. Here it is in action.
Here's something you don't want fired in your direction: a "smart" gun that fires bullets that can travel through walls, exploding once they're inside. It's the accuracy of a rifle with the explosiveness of a grenade launcher.