yes, it has doubled from 65% of GDP to 130% of GDP in the last 15 years (GFC and pandemic). Click 50Y or Max time scales for more history:

https://tradingeconomics.com/united-states/government-debt-t...

This has been growing faster than CBO projections, though obviously the last few years were unique (hopefully). Found a graph from the 2015 CBO report that is still in a wikipedia article that projected we'd be at about 75% debt/GDP now[1]. Another article from 2020 as pandemic aid spending was going out warned we could hit 106% by this year.

IIUC there's not a line that we must not cross, but the level, the rate, and the can-kicking on all this debt spending, and debt in general, worries me (even as someone who leans to the left and supports big government projects).

[1] https://commons.wikimedia.org/wiki/File:FederalDebt1940to201...

Yes, at the moment, but the trick is to grow your economy faster than your debt.

The US has managed to do that in the long term.