Though it's accuracy and power often get a bad rap, the M1 was ballistically sound for its intended purpose. The Carbine was designed to replace the M1911A1 for support troops, machine gunners, tankers and other soldiers who didn't need a full sized rifle like the Garand and is certainly a better option at close-to-moderate ranges than a pistol.
One of the most nationally recognized and the most decorated soldier of World War II, Lt. Audie Murphy, fought off a German attack on Jan. 26, 1945, pretty much by himself. He used a field phone, a .50 cal M2 Browning, and his M1 Carbine.
During the earliest fighting in the Vietnam War, the Viet Cong armed entire units using with M1 and M2 Carbines. The weapons were originally taken from the occupying French, and then from the Army of the Republic of Vietnam (ARVN).
It was the only gun made specifically for U.S. Airborne forces in WWII. A special configuration know as the M1A1 Paratrooper with a pistol grip and a folding metal stock was adopted in 1942. About 140,000 were produced during the war.
Surplus M1 Carbines are no longer available. The last big wave from Blue Sky and Arlington Ordnance came and went decades ago. In 1963, about 240,000 decommissioned M1 Carbines were sold to NRA members for $20 each.
When fitted with early, bulky M2 Infrared Sniper Scope, the M1 was actually the first night-time sniper rifle. In a configuration designated as the T3 Carbine, it was used as a night-fighting weapon near the end of the war in the Pacific Theatre. Only about 1,000 of these rigs were made, and after the war, 99.8 percent of the T3s were demilitarized by torch cutting through the receiver. That spotlight under the barrel is actually an infrared emitter lens.