The U.S. Military Intelligence Service issued the “Campaign Study” series during WWII to summarize lessons from the various campaigns. Written by U.S. observers in the Middle East, Notes and Lessons on Operations in the Middle East (Campaign Study, No. 5, January 1943) drew a number of conclusions about German and British armor operations in North Africa.
In order of importance, the desirable characteristics of armored vehicles are
(1) firepower, (2) mobilityand mechanical reliability, (3) armor.
The British infantry tank and the U.S. M4 have relatively the same armor. But the British tank with its 2-pounder (40-mm) armament is undergunned; also, it possesses low tactical mobility and is mechanically unreliable. The M4, with its 75-mm high muzzle-velocity gun is effective against German tanks, possesses high tactical mobility, and is mechanically reliable. The M4 is a superior tank; the British infantry tank, because it lacks the first two characteristics, is almost worthless except for a few special operations.
Only after adequate firepower has been provided, and a high degree of mobility, accompanied by mechanical reliability, has been developed, is heavy armor plate for vehicles justifiable. When the first two characteristics are attained, such armor as does not interfere with mobility and reliability should be placed on the vehicle.
Armor is far less important than is generally supposed. Two years’ observation has indicated that if the tank compartment is penetrated, escape of the crew is usually impossible. Even though the tank does not burn, the German shell bursts after penetration, and the explosion destroys the crew. If the tank catches fire–and this is frequently the case–escape of the crew is impossible.
On the other hand, the same field observation indicates that chances of survival in an unarmored vehicle are almost as good as in an armored one, since the moment an unarmored vehicle is attacked the crew can abandon it. The same order of importance applies even more strongly to self-propelled artillery, where light armor is desirable but not essential.
In the race between armor and guns, guns are in the ascendancy.
In 1939 and 1940, German Panzer units overran Poland and Europe; the Allies’ antitank guns could not stop a tank. In 1940, General O’Connor’s infantry tanks were impervious to Italian artillery and antitank weapons. During the past 2 years, however, in the desert and elsewhere, there has been a steady increase in the power of antitank weapons. Today both the British and the Germans have weapons which will stop any tank.
This increase in the effectiveness of antitank guns has caused the tank to become a weapon of opportunity, to be used only against objectives which it can easily and quickly destroy. In such a role the tank is becoming more and more dependent on other weapons.