The total “revenue” of the US government is $3 trillion. Therefore, more than 30% of tax “revenue” would go to pay interest on the debt alone. Obviously, interest rates rising to 10% would see well more than half of all tax “revenue” going towards interest payments on the debt alone. And at 16% the entire tax “revenue” of the US government would go to make interest payments alone. Of course, if you consider that most of the government’s debt is at the 5-10 year duration, and that typically the yield curve is positively shaped, the numbers get a bit worse.