Basically flat since the end of WWII, significantly lower before the war. At the height of the New Deal, less than half of what it is now. And that's in the face of significant growth in real GDP per capita. Probably not a dissimilar story in most other Western countries.
The problem isn't in the amount of taxes being collected, it's in how the money is being spent.
https://fred.stlouisfed.org/series/FYFRGDA188S
Basically flat since the end of WWII, significantly lower before the war. At the height of the New Deal, less than half of what it is now. And that's in the face of significant growth in real GDP per capita. Probably not a dissimilar story in most other Western countries.
The problem isn't in the amount of taxes being collected, it's in how the money is being spent.