We keep being told by the experts that Trump is a divisive figure with a low ceiling, but the ceiling keeps going higher – 22, 24, 26 per cent, over thirty per cent in the latest South Carolina poll, which is impressive in a 17-man field. But I pointed out to Sean that a lot of those other candidates are also “divisive” and have low “ceilings” of their own: Rand Paul is a libertarian isolationist, Lindsey Graham is a Big Security State interventionist – not much overlap there. How about the rest? Mike Huckabee is a Big Government social conservative, Jeb Bush is a fiscally conservative open-borders fanatic, John Kasich is a Medicare-junkie government-grower. In terms of the Reaganite trick of uniting the fiscal conservatives, social conservatives and the national-security right, a bunch of those guys come with pretty low ceilings – maybe lower than Trump’s.

The celeb candidate made news in the first five minutes by refusing to commit to supporting the eventual GOP nominee. However, he was willing to say that “if I’m the nominee, I will pledge I will not run as an independent”. So if he’s the Republican candidate he’s willing to pledge not to run as an independent candidate. Presumably, if he’s the Republican candidate, he’d also be willing to pledge not to run also as the Democrat candidate.

Sean and I analyzed the meaning of Trump’s non-pledge in negotiating terms: when the party establishment is treating you like dog feces on their shoe, why roll over and play the house-trained poodle? But, setting aside low cynicism, let’s also put it in principled terms. Parties are useful vehicles for promoting certain ideas …but they can also outlive that usefulness. Unlike parliamentary democracies, America does not have a dynamic party system. In the Canadian party leaders’ debate hosted by my old chum Paul Wells last night, there were representatives of four parties on stage: the Liberals go back to 1861; the NDP is a century younger, founded in 1961; the Green Party dates from 1983; and the Conservative Party in its present incarnation goes all the way back to 2003. I pointed out a few weeks back that in the the 1868 election every single constituency in England, Scotland, Ireland and Wales elected either a Conservative or a Liberal. Since then a bewildering variety of Celtic parties have proliferated and in England the Liberals have been largely supplanted by Labour.