Ben Lowry: Donald Trump really could get the Republican nomination

After initial protest votes in the first state contests for the Democratic and Republican nominations, the parties will rally around an establishment nominee, Hillary Clinton, and a candidate palatable to the Republican establishment, such as Marco Rubio.

That is what we have been told. But we were told that Labour would not elect a hardliner Jeremy Corbyn as leader, and it did – by a landslide.

Politics is now unpredictable in the western world. Australia has had four prime ministers in two-and-a-half years. Italy has had the same, in barely more than four years.

Voters are lurching from person to party to idea. In Britain’s general election, a once fringe party Ukip won 14% of the vote in England, while Scottish nationalists picked up half the vote there. Scotland nearly left the UK in 2014 and the UK could be out of the EU by the autumn.

In America, it is still unlikely that Sanders will win the Democratic crown, although he is giving Clinton a scare.

But it is looking increasingly conceivable that Trump might in fact prevail. He is facing so large and split a field of opponents, including candidates with hopeless prospects such as Carly Fiorina and Ben Carson, that his momentum is still at this stage growing.

It is hard to see Trump beating Clinton in a national head to head, but in the unlikely event that he was facing Sanders, the US would hardly embrace an avowed socialist.

It is still highly improbable that Trump will be president, but it could happen. Thus it was stupid for UK politicians to demand he be banned from Britain. After all, we allow a platform to Islamic hate preachers. His comments about banning Muslims were ugly and unworkable and showed his unfitness for the Oval Office, but were not even close to meriting an entry ban.