Comparing: T28 Concept vs. M56 Scorpion

The development of this heavy breakthrough tank began in September 1943. It was planned to utilize certain components of the M6 tank as well as the electromechanical transmission and 100-mm T5 gun, mounted in a turret of limited traverse with 203-mm armor protection. The vehicle was intended to assault the fortifications of the German "Siegfried Line" (known as the "Westwall" to the Germans). The U.S. land forces rejected the project during the design phase. The vehicle was later modified into the T95 heavy breakthrough tank.

The M56 SPG was intended to support airborne units as a light tank destroyer that could be transported by cargo planes or inserted by parachute or glider. The vehicle was mass produced from 1953 through 1959, but it was not popular and was soon replaced by the Sheridan light tank. The Scorpion was occasionally used to provide artillery support in Vietnam.