US government expenditure is more than $6.3 trillion. The $3.6 trillion you quoted is just federal spending, and does not include state and local spending:
So, it's more like 50-something percent, not 100%. Also, some of the money would come back as sales tax etc., so the real impact would be less than 50%.
http://www.usgovernmentspending.com/total
So, it's more like 50-something percent, not 100%. Also, some of the money would come back as sales tax etc., so the real impact would be less than 50%.