Any spending can be inflationary if it’s perceived to not be productive.
How that spending is financed is a footnote. Domestic debt works, foreign debt works, but the central bank can also purchase bonds and that works too (and is not inflationary). This is what Japan has been doing for decades to great success.
Not to say that the transition is easy, and if too much of the USs debt is owned by 3rd parties that means that there will be currency value shocks that have to be mitigated.
It does not mean that there will be a crash, or a recession, or a default.