> Why would the Fed want 5% nominal rates for 30+ years?

This is a strawman. I said nothing about the Fed wanting 5% rates.

I'm simply saying rates are not going to be higher for a LONG period of time because - if you look at the math - a sustained period of high interest rates with our current public debt to GDP means that public spending would have to fall dramatically (which would crush GDP in itself - a negative feedback loop).

Substitute 5 for any non-negative number, and you'll see that any number higher than 0 LONG TERM means a cut to public spending.

You multiply the increase by ~3.5x (to include effects from state & local governments) and then you multiply by ~4x (because taxes aren't 100% of GDP - their ~25%).

A 1% LONG TERM increase in interest rates means a ~14% reduction in public spending (with the same tax burden).

The US Federal Government is already spending about ~14% of GDP on SS, Medicare, Medicade, and Debt Service. Considering that our tax revenues is only ~17.6% of GDP. Good luck cutting spending by 14%. Let alone 2x or 3x that.