In the post-WWII era, vehicles fitting into an "assault gun" category were developed as a light-weight, air-deployable, direct fire weapon for use with airborne troops. Those weapons were either based on jeeps or small tracked vehicles and the airborne troops thus always fought at a distinct disadvantage in terms of heavy weapons. The Soviet Union and the United States were the most attracted to the idea of providing this capability to traditionally light airborne forces. Their answers to the problem were similar, with the United States developing the M56 Scorpion and the Soviet Union developing the ASU-57, both essentially air-droppable light anti-tank guns.