Below is a quote from Josh Marshall from Talking Points Memo.
I think he hits the nail on the head on Trump and foreign policy:
His language has a recurrent focus on foreigners and foreign countries 'laughing at us', 'humiliating us', 'beating us.' This is not the prism through which peaceful coexistence, even undergirded by military strength, is built. It's a language of revenge. [...]
In the Trump foreign policy worldview, we, the United States, are the unmanned losers that guys like Trump stomp and humiliate. We've become a nation of Jebs in need of a Trump to lead us. We need a Trump-type president to move back to dominating rather than being dominated. To imagine that this leads to a judicious, even-keeled foreign policy is the height of delusion. [...]
Consider Trump's infamous and ridiculous US-Mexico border wall - that Mexico is going to pay for. This is such a nonsensical proposition on so many fronts that few look at it seriously. But here's the thing: Mexico paying for the wall isn't a matter of cost-saving or fairness or equity; it's a symbol of humiliation.