Even Buchanan does not get it.
The major issue is not whether he wins, but why is he getting so much support. Putting aside all the girlish shrieking about "the Trumpening," the reality is the Trump is a fairly lousy candidate: an obnoxious buffoon, a realty show star, ill informed, whose views on legal immigration are questionable, whose daughter is married to a Jew, etc.
But he is by far the best of the bunch, and the only one who can be called a "right-wing populist," despite his pro-fatcat economic views.
Thus, the real meaning of Trump is that the GOP White voting base is beginning to stray off the reservation; the natives are getting restless.
Sure, the base is still stupid and feckless: see the support for Carson, and note that most of the base will rally to whoever the GOP nominee will be, even if Jeb or Marco. But, still, the enthusiasm for Trump, which puzzles the Establishment, is a clear sign that the base is at least beginning to wake up, although this process may take altogether too long (and could become channeled in counter-productive directions).
Nevertheless, it is NOT business as usual in American politics. One wonders - if Duke was running this year, how much support would he get?
And all the talking heads who assert that "the GOP could win the national election in 2016 by shifting left on immigration" still don't get it. Yes, most of the stupid base may still come out to support that, but enough may stay home to ensure a Democrat victory.
At some point, even dumb Whites can't continue to be fooled all of the time.