"I think many here in UK are very much afraid of what Trump might provoke regarding starting wars and alienating other nations."

Over here, too.

I'm afraid, though, that replacing him with someone less foul-mouthed and belligerent might not necessarily work.

As a Republican, George W. Bush was a centrist. His family did not endorse Trump and probably didn't vote for him. But by the time he was as deep in his term as Trump is now, he and his crew had spent months laying the groundwork for the Iraq invasion. (Which Clinton, Trump's opponent, and a rather hawkish Secretary of State herself, initially supported.) So Bush may have actually been more dangerous in his first year than Trump has been, despite his mouth. Let's hope so. Trump would have to go some to accomplish as much harm as Bush eventually did, but he's certainly capable.

I'm afraid, and I apologize for it, that the US threats to global security can't be resolved by getting rid of the obvious rotten apples.