Trump seems to me like a genuine nationalist.  A year or two ago I was dead set against nationalism due to the very ugly history of what it can create.  OTOH, I always did have a soft spot for nationalists in most other countries who took an interest in trying to benefit their own people rather than wealthy forigners using the resources of their own country (esp, Chavez, Putin, etc.)

Over the last few years I've come to consider the United States itself as being an underdog who is under effective attack from the globalists.  Not the soft-globalists who want international cooperation but the hard-core globalists who want corporate owned technocratic one-world central governance.  This, to me, the worst thing in history.  I have continued concern about Trump's penchant for authoritarianism and limited interest in 'individual liberty', but feel that we (all societies) must stay wired for a multi-polar world with a diversity of visions or all will be lost with no realistic avenue for recovery of those things which Trump and his ilk might be weak on.

I'll add one thing.  As programers and systems analysts who strive for efficiency know, systems need to be 'normalized' in order to have things work smoothly.  The gears need to mesh.  This is exactly what the globalists are doing at the moment.  Trade is one of the primary tools to make this happen and it is no accident that there are huge deficits and 'bad deals' for the United States.  Trump hammers on this and in pubilic writes it off to 'stupidity' within our government, but certain things he says lead me to believe that he rather thinks that it is the easiest thing for Joe Public to understand and the most effective to win votes and that he knows with some precision what is actually going on.  Hopefully also he would be inclined to fight back against some of the most powerful people the world has ever seen.

I would also say that I fully recognize that the U.S. has 'got it good' compared to most other nations, and to some extent at their expense.  This sucks for them, and it is not the reason I have an 'America first' posture.  I would like it if the U.S. could and would 'be all that we can be' without exploiting and degrading others.  Isolationism is the most likely way to achive this and I think that Trump is genuine in his stance toward this.  I would not bet the farm on it, but he seems our best hope in this regard.