Question

How did Shay's rebellion convince enough people that the Articles of Confederation had to be replaced.

Answer 1

It exposed the fact that the Articles of Confederation did not have much military power. Shay's Rebellion would not have been as terrible if the Articles simply summoned an army to stop it, but they did not because of their lack of authority. Instead, local militias had to step in and stop the rebellion. This would lead to the US Constitution being allowed to summon the military in the situation of combat.