The US military relied on air superiority during World War II. Anti-aircraft defense of the troops provided towed cannons, or. self-propelled anti-aircraft devices M16 MGMC on halftrack landing gear. Only at the end of the war did the anti-aircraft tanks M19 with a double cannon Bofors caliber 40 mm on the chassis of the M24 Chaffee tank get into production. However, the end of the war caused less than 300 pieces to be built.
In the late 1960s, the US Navy began looking for a weapon to protect its ships from specially designed anti-ship missiles. They realized that standard medium- or long-range anti-aircraft missiles or classic small-caliber rapid-fire cannons were not capable of destroying such targets and thus fully ensuring the protection of vessels.