Since early times, horses have supported mobile, lightly armored combat via chariots or mounted knights. Later, internal combustion engines and tractor treads enabled rapid off-road movement of heavily armed and armored vehicles. Called tanks, these craft decisively affected many land campaigns, especially in World War II (1939–1945); but their expense, weight, and complexity often created controversy over their proper use and future existence.

Salem Press Encyclopedia, 2023. 3p.