Initially designed to save lives, the modern machine gun can destroy the enemy from more than a mile away and can fire 1,200 rounds in just 17 seconds. How did the machine gun become one of the most powerful Machines of War? NGC explores its 150-year history and evolution from the 19th-century machine gun that can chop down a single tree, to the first gangster "hit" with a Tommy Gun, to one of the deadliest weapons in the world.