US election 2016: Iowa primary arrives with fringe candidates, but we should let moderation prevail

Will Sarah Palin, Mike Tyson and Hulk Hogan swing it for The Donald? Mr Trump, who has enjoyed a barnstorming (if silly and offensive) campaign, will be hoping so. Strange as it may seem on this side of the Atlantic, such endorsements only add to Mr Trump’s appeal as an “outsider”, a rebel with a cause. As with so many of his apparently off-the-cuff “gaffes”, there may be more calculation in such Trumpery than meets the eye.

In any case, on 1 February the Republicans and the Democrats of Iowa will be voting for their choice for the nomination for the presidency. Iowa is, numerically, insignificant, but as the first major public election of the 2016 presidential contest, it finds itself once again in the crucible.

The signs are that this first round of a very long process will be polarising. Mr Trump has suffered little real damage among Republican loyalists for his insults and attacks on the vulnerable, the media and, indeed, Britain. Given his seven-point lead over the next placed candidate, Ted Cruz, it seems Mr Trump will be off to a solid start.

This is a remarkable achievement. Only a few months ago, Mr Trump was written off as a risible contender for leader of the free world, with his ridiculous hair and even more ridiculous policies, if we can dignify them with such a name. Almost out of cussedness, though, his own party has learned to like this “authentic voice”. He has long since overtaken the former favourite Jeb Bush.

Mr Bush has suffered from his family connections, rather than benefiting from them. Given the demographics of American elections, where the centre ground “swing” voters are increasingly the Hispanic community, the Republicans might do better to opt for Marco Rubio, the son of Cuban immigrants, rather than a man who describes Mexicans as rapists.

This points to the problem with caucuses and primaries dominated by party activists: ordinary voters don’t get a say. Of course, like Richard Nixon and Ronald Reagan, Mr Trump could win the nomination by pandering to the right but, in office, prove a more pragmatic leader than any would predict.

On the Democrat side, there is also some lurching: Iowa will not set Hillary Clinton off to a flying start. Bernie Sanders – virtually a Maoist by US standards – is only a few points behind her. Though most Americans may not have heard of Jeremy Corbyn, his victory in the Labour election potentially prefigures a similar leftist, anti-establishment insurgency.

Studiedly moderate, Ms Clinton seems to present a cautious “business as usual” brand. With close links to Democrat predecessors as wife, secretary of state and senator, she couldn’t be more of a DC insider. Like Jeb Bush, she has a famous name that has proved a wasting asset. Dynastic politics, an inferior variety of establishment politics, is doubly unpopular.

Americans could even wind up with a Trump-Sanders contest. That would make for entertaining coverage, but leave many wondering what they did to end up so disenfranchised. The rest of the world may be a little bemused too.