The question came up in a discussion with RP Eddy on Facebook, why does Donald Trump, a master of brand and marketing if there ever was one, is so against building the international brand of the US, through ‘soft power’ of diplomacy and international relations.
The answer, I think, is that Donald Trump believes that America’s ‘soft power’ (its influence and ability to get things done where others can’t) derives from its latent ‘hard power’ (the fact that America keeps a powerful military on alert, worldwide). In fact, this is not true, and the reason for America’s influence is that the US is basically trustworthy in its international dealings and follows through on things it says it will do (it is far from completely trustworthy, but maybe 60 or 70 percent of the time, it carries through which is still a lot better than the international batting average. This is not because of moral superiority, by the way, but that the US has many resources to draw on, and considers its options and its actions quite carefully.)
If Trump, as president, believes American soft power mainly derives from military power, then as a new president, he has to demonstrate that power somewhere to prove that he is ready to use it.