European doctrine
The North German Plain, gunnery culture, and several answers to the same map.
Germany: the duel at range
Bundeswehr tanks trained to kill the first T-72 at 2,000 m from a prepared position, displace, and do it again. Leopard 2’s L/55 and fire control are that idea in metal. After 1990 the same hulls grew urban and expeditionary kits (A7) they were never designed for.
Britain: stay alive, then HESH the building
Chobham / Dorchester armor and a rifled 120 mm that still fires HESH. British armor expects to take a hit in a defensive battle and keep the crew. Challenger 3’s move to a smoothbore is a logistics surrender to NATO, not a change of religion on protection.
France and Sweden: other maps
France planned for independent operations in Africa as well as Europe — hence a lighter, autoloaded Leclerc and before it the thin-skinned AMX-30. Sweden planned to hide S-tanks in forests and shoot from reverse slopes, so it omitted the turret. “European doctrine” is a family of answers to geography, not a single manual.