Correct me if I’m wrong.
The current administration cuts the tax rate and borrows to make up for the shortfall in tax revenue.
All this is in hopes that the economy grows enough such that the reduce tax rate can support government spending and pay back the debt + interest.
If the economy goes south for whatever reason (e.g. China imploding, another bubble pops) ...
Plus other countries always need to borrow dollars because it's what oil is sold in, which is one of the things that makes US Government debt considered the baseline or "risk-free" investment, with any other investment having increased risk, and accordingly increased reward.