What event showed that the Articles of Confederation could not protect the U.S.?

One event that showed the limitations of the Articles of Confederation in protecting the United States was the Shays' Rebellion. In 1786, a group of farmers in western Massachusetts, led by Revolutionary War veteran Daniel Shays, revolted against the state government due to their economic hardships and high taxes. The rebellion aimed to prevent foreclosures on their lands and to protest against economic inequality.

However, the national government, operating under the weak Articles of Confederation, was unable to effectively respond to the rebellion. The national government lacked the power to raise an army or impose taxes, and therefore had limited resources to address the situation. The inability to maintain order during this rebellion highlighted the weaknesses of the central government under the Articles of Confederation, ultimately leading to calls for a stronger federal government and the subsequent drafting of the United States Constitution.