One part of me says that the rest of the world needs to do "something" about this idiot before its too late and he really can strike anywhere in the world
Another part of me is horrified by the implications of just what that "sometihng" would need to be.
I think we have little choice but to live with it.
In terms of military action, no country in the world, and possibly all of the countries put together, are in a position to replace the US government forcibly. Maybe that will change one day, but right now, the "regime change" solution is unthinkable.
Economic sanctions? The US is a big country, and foreign trade is a relatively small part of its GDP. Sure, trade sanctions would hurt, but would it be enough? Look at how sanctioned Iran and North Korea have been, for years, and it hasn't dissuaded them from pursuing the things that are getting them embargoed. Besides, this idiot largely campaigned on a promise to put a trade embargo on the US; so how threatening would it be to him for the rest of the world to threaten to do to the US what he has promised to do to the US himself?
Diplomacy? The US isn't an advice-taking sort of country at the best of times, and even less so under its current Führer. Their attitude is, we tell the rest of the world what to do, and they do it, or face a range of sanctions up to and including military action and overthrow of their governments. I don't think politely asking the US to behave better will have much effect.
Bad as the situation is, I think we have little choice but to live with it.