Final answer:
The M.A.I.N. causes of WWI were Militarism, Alliances, Imperialism, and Nationalism. The U.S. got involved in WWI due to the Zimmerman Telegraph, sinking of the Lusitania, and economic interests.
Step-by-step explanation:
M.A.I.N. Causes of WWI
The M.A.I.N. causes of World War I were Militarism, Alliances, Imperialism, and Nationalism. Militarism refers to the arms race and the belief in the power of military force. Alliances were formed between different countries, creating a complex web of connections. Imperialism involved the competition for colonies and resources. Nationalism led to a strong sense of pride and loyalty to one's own nation.
Reasons for U.S. Involvement in WWI
The U.S. got involved in World War I primarily due to the Zimmerman Telegraph, which revealed Germany's plan to ally with Mexico against the U.S. Other reasons included the sinking of the British passenger ship Lusitania by a German submarine, and the economic interests of the U.S. in Europe.
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