This is preaching to the choir. Assault rifles are becoming increasingly popular with Americans — and no one’s giving them a helping hand like the U.S. Army. The Army runs assault rifle workshops tailored for kids aged 9 to 18, teaching skills that blur the line between marksmanship and combat training. Critics say the workshops send the wrong message, given the popularity of assault rifles with mass shooters. But the Army training’s popularity suggests the next generation of gun enthusiasts will have a more casual relationship with weapons of war.