The Biggest Strengths And Weaknesses Of America’s M4 Sherman Tank When the U.S. got involved in WWII, one thing it had in short supply was tanks. The M2 failed to meet expectations, becoming obsolete right off the assembly line. It wasn’t used in combat operations, while its successor, the M3 Lee was used as a stopgap measure while the development of another tank commenced. That replacement armor was the M4 Sherman, and it became the workhorse of the U.S. Army’s armor units deployed throughout the theater of operations of WWII. Designers used what worked and abandoned what didn’t from the…