Evolution of Tanks: USA (From WW1 to WW2)
Background
During World War I, the USA was a member of the Entente Powers. Unlike France and the British Empire, the USA produced no tanks. As a result, they chose to start the mass production of the French Renault FT tank, which is called M1917; this marked the start of US tank development.
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Interwar Period
After World War I, Dwight David Eisenhower and George Smith Patton started their mission to develop armored troops for the US Army. However, many senior military officers opposed the use of tanks to fight independently, as they thought tanks should be used to support infantry. These opinions directly caused the US Congress to dismiss the tank corps of the US Army.
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At the same time, the United States Department of War requested the design of light tanks with weights lighter than 5 tonnes and medium tanks with weights lighter than 15 tonnes. However, the failed M1924 tank proved that the request was impossible to finish. Many designs were rejected during this period.
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Finally, in 1931, Douglas MacArthur started to promote mechanization and motorization in the army, especially for the cavalry to replace horses. Then, in 1936, the new “car” research started (“tanks” were still not allowed to be built according to the 1920 National Defense Law). There were some “combat cars” produced in the late 1930s, including the T7 and M1/M2; they all used machine guns as the main weapons.
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World War II
I. Light tanks
a.) M3/M5 Stuart
During the Battle of France, which started in June 1940, US investigators found that the M2 light tank used by the UK and France could be easily destroyed by German tanks. As a solution, new light tank designs—the M3/M5 Stuart—rolled out in March 1941 and 1942 respectively. Stuart tanks have better armor and a more powerful 37mm cannon compared to the M2.
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b.) M24 Chaffee
In 1944, the M3/M5 Stuart was too outdated to be used. The M24 Chaffee was then developed to replace Stuart tanks; it has a more powerful 75mm cannon. In November 1944, many Chaffee tanks were sent to Europe and North Africa. However, it did not make many contributions to the war as only some Chaffees entered the war, and some tank divisions were still using old M5 Stuarts as light tanks when the war ended. Most Chaffees joined the Korean War in the 1950s.
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II. Medium tanks
a.) M3 Lee/Grant
M3 Lee is a medium tank that started being used in 1941. The tank is named after famous generals during the American Civil War, which are General Robert Lee (American version of M3) and General Ulysses S. Grant (British version of M3). The main difference between M3 Lee and M3 Grant is their turret, which is quite easy to identify. Both versions of the M3 were armed with a 37mm cannon on the turret and a 75mm cannon on the hull, as well as a small turret for machine guns above the 37mm cannon turret. Although the M3 has relatively thick armor, it has some drawbacks such as a high hull and bad mobility. Also, as its 75mm main gun is located on the hull, the power of the tank is limited. It was soon replaced by the M4 Sherman. The photo below shows both the M3 Grant (left) and the M3 Lee (right) so you can easily see their difference.
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b.) M4 Sherman
M4 Sherman is one of the most famous tanks ever, with more than 48,000 produced; it served in many countries including the UK, France, and China. It also has many variants. I will introduce some here. The first one is the M4A1, which is the basic design of the Sherman tank. It was armed with a 75mm cannon (yeah, Americans use a 75mm cannon throughout the war). Some were then changed to a 76mm cannon, providing better firepower, and were called M4A1(76w). At the same time, the M4A1 tank is also infamous for its poor armor, so it has the nickname “Ronson” (a lighter produced in Germany) as it can be easily destroyed and catch on fire.
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The next one I want to introduce is the M4A3E2 “Jumbo”. As the M4A1 and M4A2 tanks could not withstand attack from German tanks such as the Tiger and Panther, the US Army tested a new tank using the hull of the M4A3, which has the best protection among all Shermans. Additional armor was attached to the hull and a new turret was used. After modification, the tank can withstand Germany’s strong 88mm cannon and 75mm cannons. Same as other Sherman tanks, the M4A3E2 has both a 75mm cannon version and a 76mm cannon version (M4A3E2 76(w)).
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Not only the two variants I introduced, there were a lot more variants such as the M4A2, M4A4, M4A5, and Sherman Firefly (used by the British army), etc. We can see that the Sherman is one of the most successful tanks produced.
III. Heavy tanks
a.) T1E1/M6A1
The T1E1/M6A1 heavy tanks were prototypes of the US Army designed to test heavy tanks, as many countries at that time were already producing their heavy tanks, such as the KV series of the USSR and the Churchill series of the UK. The T1E1/M6A1 tanks were armed with a 76mm main gun and a 37mm gun. Only 40 tanks were produced, and they never joined any battle.
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b.) M26 Pershing
M26 Pershing is a heavy tank (reidentified as a medium tank after WW2) used by the US Army. It started mass production in 1944, and hence a limited number of them joined battles. Like the M24 Chaffee, most Pershings joined the Korean War instead. Pershing had excellent armor at that time with its powerful 90mm cannon, which made it the second-best tank in WW2 (just under Germany’s Panther). Pershing also had many variants such as the Patton series (M46, 47, 48), which was the main power of USA tank forces for more than 50 years.
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IV. Conclusion
Although the USA started its tank development late, the country still brought out many excellent designs that influenced the world and also made many contributions along with its allies to fight the Fascist powers in WW2. Overall, the US created a unique style of tank designs and has had a great influence on modern tank design.