Ben Lowry: Make no mistake '“ Corbyn could easily become PM in a fresh election

Those two electoral earthquakes shattered conventional political wisdoms, but there is a specific foreshadow of the rise of a firmly left-wing politician – Bernie Sanders.

Sanders narrowly lost to Hillary Clinton in the primary race for the Democratic Party nomination for president but might have won if wavering Democrats hadn’t feared he was unable to beat a Republican Party candidate in November’s election.

Sanders has long described himself as a socialist, a once toxic label in America. Even though my own politics was in transition from left to right by 1990, I was delighted that year when Vermont (near my birth state, Maine) elected him the only socialist out of 535 House Representatives or Senators.

It seemed absurd that a great democracy had hitherto been unable to tolerate that viewpoint. But it was still clear that anyone associated with socialism could get nowhere near the White House – until last year, when he did so well.

There are plausible arguments, too detailed to cite here, that Sanders would have done better than Clinton against Trump. Americans under 35 do not remember the Cold War or fear ‘reds’ as their elders did so I think he might have clinched the Oval Office.

Recently I interviewed Yanis Varoufakis, the leftist former Greek finance minister, and he said the electoral turbulence in the West is fallout from the financial crisis.

Consider a right-wing policy I have advocated for years: the overhaul of the welfare state. Despite reform to date, I think that hundreds of millions of pounds is still squandered on lifestyle choices.

Yet however bad the worst benefits abuser, many bankers behaved far worse, but were bailed out by the taxpayer and are back earning obscene bonuses. It is a major moral failure that so few bankers were jailed after 2008.

No wonder Corbyn and Sanders have such appeal.

An irony of Corbyn’s rise is that there is inter-generational unfairness in Britain, in which older people have done better than younger folk, and that is helping Labour at the polls, yet many Tory policies (including its disastrous, but brave, social care plan) tried to rectify that.

Some pundits have not grasped what happened on Thursday. On Friday night’s Question Time, the journalist Isabel Oakeshott scoffed at the idea that Britain would elect Corbyn prime minister.

Such talk implies that while Corbyn reached a level that almost no-one foresaw, the pundit has somehow divined that he is now at a ceiling beyond which he cannot go. Yet with a 1.2% extra Tory to Labour swing, Corbyn would have outpolled Theresa May.

The vote was so close (40% Labour, 42% Tory) that Mrs May is lucky to be well ahead in MPs. A seat allocation proportionate to votes would be Tory 298/Labour 281 (Corbyn able to form a rainbow coalition).

The first-past-the-post system is such that, depending on vote distribution, he could even have won most seats on fewer votes than the Tories.

Stunning things happened. In London 10 days ago I was astonished by polls showing that the Tories had gone from being 4% behind Labour in the capital to 17%, and sure enough the party was almost wiped out there.

This was in part a Remain protest vote, which went to Labour even though it pledged to implement Brexit.

If in a future election Corbyn is just shy of a majority, it could tempt Sinn Fein to abandon abstentionism in order to install him in Downing Street.

If he implemented joint authority (which would be a compromise for a man who has long backed Irish unity), it would never be reversed.

If DUP negotiators are aware of this possibility, they will know not to play hardball with a Tory Party that is one of their only possible allies at Westminster.

• Ben Lowry (@BenLowry2) is News Letter deputy editor

Ben Lowry June 9: New influence for the DUP but it needs to tread with tact and caution at this perilous time

Ben Lowry June 7: Even if Corbyn loses badly, Labour’s vote rise seems set to rise, which would be a huge result for him

Ben Lowry June 8: Exit poll at Elmgrove in East Belfast shows huge vote for DUP