Most of the tanks shown are M2 Light tanks used sparingly after war was declared. Under-armored, under-powered and under-gunned, it would have performed poorly against enemy armor. It's gasoline engine was far more susceptible to catching on fire than German tanks with Diesel engines. The only combat action the tank saw was on Guadacanal with the Marines in the Pacific Theater. Otherwise, they were used for training only. 698 were made from 1935 to 1942.
The triangular patch the soldiers are wearing on their left shoulders is for the 1st Armored Division that had just been activated at Fort Knox on 15 July 1940. Its first action would be the invasion of North Africa in Novebmer of 1942. As of 2021 the division is still active and has been stationed at Fort Bliss, Texas since 2011.
The gas mask training sequence showed African-American recruits, although the Army remained segregated until 1948. The platoon shown was segregated.
Veteran character actor George Tobias is perhaps best known from his stint on TV's "Bewitched." He played the long suffering husband of Gladys Kravitz, Abner.
This film was released October 4, 1941, two months and three days before the December 7th Japanese attack on Pearl Hatbor that thrust the United States into World War II.