That's a tough question, so I'll try to build on a possible scenario that includes the largest factor that was supposed to be kept secret from Americans. That is of course, the fact that Kruschev knew that he was justified because of US attempts to pose the same threat to the S.U. in Turkey and possibly Italy.
So first the question on whether or not Kennedy was responsible for the decision to risk nuclear war. I would suggest that would be a matter that would be above the pay grade of any president. It's a purposeful illusion created by the US to make it appear that the president has made a decision. That's now well known to America's enemies, thanks to their mentally ill president!
And so in the case of Trump, it would be even more important that Trump would be of no importance in the least on how he thought or felt. And so, we would need to consider the feelings and opinions of those minds who have the power to make decisions within the Trump regime.
In my opinion it's always going to boil down to the question of M.A.D. being considered and US decisions being made on that basis.
US foreign policy isn't in the hands of their president (commander in chief bullshit). On those matters of great importance, the president is a figurehead. How could anyone not understand that in the case of Trump?
Do you agree? Your opinion?
I do think Trump is operating out of his depth (facial appearance suggests high performing downs syndrome maybe). I also agree that he might be mentally ill.
If Trump is of no importance in the decision making of the states, it might explain some things.
If he was to be put under pressure, just how irrational would he become, would he go MAD, and need locking up, or would he agree to lock himself up, and Tweet anything that comes into his head, whilst the real decisions are made for him.
As a spokes person for the USA, he appears to be a bit lacking in many areas of understanding. Who would want to be lead by an ignorant person. He does appear to have the power to fire his advisers and get votes, maybe he appeals to the ignorant majority of voters in America.
I think that the question on Trump's behaviour concerning trade with other countries can be answered in the same way that military matters are handled concerning American's enemies. It's also above Trump's pay grade.
It can be measured in how cautious Mnuchin and others are in keeping Trump thinking that his opinion matters.
On Brexit: I know very little on the details because I haven't found it of much interest. The reason for that lack of interest is because I would consider that Putin would be displeased on seeing the UK leave. The US will be able to benefit from a stronger and greater alliance with the UK.
Of some interest though, we already see Germany failing to abide by US demands against Russia and China.
You wrote: "I do not see China as a threat, except to fair trade. (they are known not to play fair ) Copyright to the Chinese, I suspect means they have the right to copy a product."
With due respect to your opinion, I see it as just sour grapes by the US and nothing they wouldn't do themselves with impunity.
Why would you think that Germany or any other country comply with demands from an outside power, all countries in the world are free to trade with who they like. China is a huge market place, and is going to overtake the USA in trade with the rest of the world, Europe is also a big market place. Crying fowl and changing the rules of play, when you are losing might be what Trump is trying to do.
Regarding Trade agreements, they take a long time to set up with mutually agreeable terms for trade. New agreements are not drawn up over night.