Is there really any correlation between tax revenue and spending at the federal level anymore? It seems the U.S. government is willing to spend at huge deficit levels. If everyone stopped paying federal taxes I suspect nothing would change.

What would change is the government would need to greatly increase their debt. In 2025 the government got about $5.23 trillion in tax revenue and spent about $7 trillion. So most of the government spending is financed by taxes. Remove that and the rate of debt quadruples (and by extension inflation).

Magical thinking! You may as well recommend the government prints more money and give it to everybody...

In FY2025, the U.S. federal deficit was $1.78 trillion, with total revenue at $5.23 trillion, so clearly it's a majority of revenue.