> There's no chance US will default on its debts,
Why not? It has happened* before therefore it can/will happen again.
* (more or less). I would count significant debt restructure (1790) or replacing promised gold with paper (1860-1930, 1970) or even a significant delay (1979) as a default... even if it was temporary in 1979.
None of those were defaults. The US has never defaulted on its debt, as never did Germany or Italy (speaking of state issued bonds, not war reparations).