Trump and Bolton never seemed that good a fit. Bolton is a Bush era war horse who thought international problems could be solved by dropping bombs all over them; Trump, on the other hand, is a used-car salesman who believes in the "Art of the Deal". It may well be that Trump hired Bolton in the first place not because of what he stood for but because he liked his style as a Fox News commentator. Bolton, with his Mark Twain hair and moustache, certainly stands out in a crowd.
Say what you like about Trump, but he's not a war-monger. And waging war is the greatest crime any human being can commit. It subsumes all the rest. Send in the troops and you've granted license for murder, theft, rape, arson- the works.
There may be such a thing as a "just war"- but the longer I live the less convinced of it I am.