The billion dollar question in my mind is what external force stops the borrow-and-spend binge. Maybe once the Fed owns 30-40% of the "treasury market" - at that point we will have gone full Japan and there will be no treasury market, other than what the Fed has cornered. Once whatever is left of the "market" for US treasuries catches wind, they'll sell into the Fed's bid.

This could accelerate rapidly and happen very fast, possibly during the Xiden-Fellatrix administration.