If isolationist Trump is elected, expect Japan, South Korea, Poland, the Nordic countries maybe together with the Baltics - and Australia to be forced to acquire nuclear weapons and the means to deliver them to their targets in Russia and China. That would be a serious warning against having a single point of failure when it comes to strategic deterrence.
When the bombs drop - I hope they hit my house.
The way to stop that is to elect a non-Trump. In this case, that someone would be Joe Biden despite him falling short of successfully calling out Trump's non-stop stream of lies yesterday. Many America Firsters don't understand one thing, which is that if isolationism wasn't workable a century ago, it will be even less workable now. This is because of global nuclear proliferation. If nuclear threats are seen as a working foreign policy tool, you can rest assured all manner of rogue states will try that, forcing everyone else to get their own nukes if the US abdicates its role as the provider of a nuclear umbrella for the West.
Trump's previous term was a bit of a shit show only salvaged by the adults in the room so to speak. Trump has vowed to kick them all out of all government bureaucracies in his quest to destroy the "deep state". God help us all if that unhinged idiot is elected.