Only if we prepare for it. A couple of international treaties created the current international order with the US dollar as the world reserve currency. That in combination with the massive US market allows the US to deficit spend to the extent that we do.
But with that came the expectation that the US was going to be the "world policeman."
If the rest of the world wants to dump the US, the US should strengthen its military (not just rebuild the war weary force) and do what it takes to bring industry back to the US. Once we do that, if the world drops the US, the US can erase all debt owed to anyone not a US citizen, corporation, or lawful permanent resident.
If the US is well prepared the resulting global economic crash won't matter to the US- we can be totally self sufficient.