When we became a debtor nation, we sewed the seeds of China being in a position to hold power over us. We became dependent on other nations to finance our debt and continued spending. And if they stop purchasing our treasuries, bonds... we’re in trouble. That’s my take on it.
Followed quickly by them. We are in the same boat and mostly economic allies at this point (mostly against Europe). A lot of people get confused about their need to overcome American hegemony in their locale and think that they want or have to tank our economy to do that. A more likely alternative is that they will cooperate economically for quite a while as they build up their military and influence.