Oh no there would absolutely be responses, but not to the level of military retaliation as he was suggesting.

China would definitely use it as an excuse to build up their nuclear stockpile and the nuclear test ban treaty would be in tatters.

It would also result in a lot of civil unrest in the US which could spiral into a civil war. To be honest though I can’t really see the US surviving until the end of the century regardless, there’s just too much hate and division there and neither the republicans nor the democrats have ever attempted to fix major societal issues.