Has he ever used his billions to champion any kind of discernible core principles?

National Review Online has been pretty uniformly against Donald Trump's campaign (for which it has LITD's admiration). Lots of its big guns - Rich Lowry, John Fund, Mona Charen, Jonah Goldberg - have weighed in.

For my money, the most razor-sharp arguments have come from the great Kevin Williamson, who contributes another salvo to the cause today.

He expresses his dismay with the fact that one in five Republicans is in this charlatan's camp, and then takes on the "we're-behind-him-because-by-God-he's-a-fighter" reasoning they so often toss out in defense of their position:

The Trumpkins insist that this isn’t about Trump but about the perfidious Republican establishment, which is insufficiently committed to the conservative project. Fair enough. But what of Trump’s commitment? Being at the precipice of his eighth decade walking this good green earth, Trump has had a good long while to establish himself as a leader on — something. He isn’t a full-spectrum conservative, but he seems to have conservative-ish instincts on a few issues. What has he done with them? 

Williamson cites some other billionaires who have used their fortunes to speak for things they stand for.  The most relevant example he offers is the Koch brothers, who have financed such free-market organizations at the Cato Institute and Americans for Prosperity.  They have written about the free market as the obvious solution to what vexes the economy in various journals.

Trump has written many books as well. What is the common theme running through them? Basically it's "protect your brand, cultivate ruthlessness and arrogance, and view everyone and everything that is not you in terms of how it can be leveraged for your advantage.

This man must never be US president.  Meanness and solipsism are immediate disqualifiers.