The major downfall of the Articles of Confederation was simply weakness. The federal government, under the Articles, was too weak to enforce their laws and therefore had no power. The Continental Congress had borrowed money to fight the Revolutionary War and could not repay their debts.
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Based on the research that I did it seems that poison gas is the most factually proven one although I am not 100% sure.
The help with the federal law and deal with the era
Answer:
Hero of democracy:
1. Centralized the banking system
2. Supported education-based on merit
3. Took first steps towards democracy.
4. Instituted civil code.
5. Believe in equal taxation.
Enemy of democracy:
1. Believed in no equality between sexes.
2. Disregarded civil rights.
3. He was a tyrannical leader.
4. yellow journalism/propaganda reform.
5. Forced people into the army.