Why was the resolution of the federal government’s fiscal problems so critical to the success of the new nation?

Because the federal government was bankrupt, and without solving its fiscal problems, it could not raise an army in case of invasion from foreign powers, like Britain or Spain.

This is why the US constitution gave the federal government the faculty of raising federal taxes, in order to raise the necessary amount of money to protect the union.

c-three

explanation:

legislative, executive and judicial