Turrets, which had always been considered, but were not previously a universal feature on tanks, became recognized as essential. It was appreciated that if the tank's gun was to be used to engage both 'soft' (unarmored) and armored targets, then it needed to be as large and powerful as possible, making one large gun with an all-round field of fire vital. Also, mounting the gun in a turret ensured that the tank could fire from hull down cover. Hull-mounted guns required that most of the vehicle be exposed to enemy fire. Multiple-turreted or multi-gun designs such as the Soviet T-35, American Medium Tank M3, French Char B1 or British A9 Cruiser Mk I slowly became less common during World War II. Experience showed that a tank commander could not effectively control the fire of several weapons; also, the newer dual-purpose guns eliminated the need for multiple weapons. Most tanks still retained a hull machine gun, and usually one or more machine guns in the turret, to protect them from infantry at short range.