1) Don't underestimate the ability of misguided xenophobic nationalism to carry a national election. This is something for cocky American progressives to keep in mind as we face down a Donald Trump candidacy. Just because it's a really stupid idea doesn't mean it won't happen. And in this day and age, one makes a very serious mistake regarding the sentiments of the right-wing rank-and-file if one only pays attention to the opinions of the right-wing elite. The latter are rapidly losing the grip on the former.
2) A Jeremy Corbyn style left is utterly incapable of standing against this sort of tide. This is true for many reasons, but the primary one is that the sort of conspiracy-laden thinking Corbynistas like to indulge in isn't really that different from the instincts that motivate their right-wing counterpart. Ultimately, they share a sense that "Real