Bernie Sanders makes me wish I was 20 again, just to experience the sweetness of first political disappointment

What the middle aged smugly know as naive idealism is the recognition of simple truth

Bernie Sanders contests the Democratic nomination in the 2016 race for the White House. (EPA)

On first viewing, the mad professor figure of Bernie Sanders might pass for a character in a low budget satire about the shimmering insanity of US presidential politics.

Finding the actor to play the Vermont senator, who despite beating Hillary Clinton by huge margins in all three of Saturday’s caucuses has almost no chance of the Democratic nomination, would be a cinch. Larry David is eerily cast to type by looks (white haired baldie), background (Brooklyn Jewish) and temperament (droll irascibility), and has already played Sanders in Saturday Night Live sketches.

On closer inspection, Sanders is the only serious candidate on view in a campaign season that doesn’t get less crazy. The latest episode from the Republican plaground finds them scrapping over whether Donald Trump planted the National Enqurier story about Ted Cruz seeing more extramarital action than seems credible for so repulsive a specimen.

This followed Trump juxtaposing pictures, on Twitter, of their respective wives - the unwritten commentary being “My missus is smokin’ hot. And yours, Lyin’ Ted ….” That itself was a counterstrike, after Cruz supporters released an advert featuring an old photo of Melania Trump, a one-time supermodel, notably short on garments. Thus do the would-be inheritors of Lincoln’s mantle demonstrate their fitness to lead the free world.

As for the still prohibitive favourite for the Democratic nomination, admittedly there is little amusing about Hillary Clinton. It is true she has appeared on SNL playing herself, gamely colluding in a parody in the hope of narrowing the likeability gap. Even so, only the most sardonic etymologist would argue that her first name is a contraction from “hillarity”.

Yet being dogged and resilient, grave and unsmiling, shouldn’t be confused with being serious. In fact there is something facetious about the glibness with which she explains her support for the Iraq folly, and justifies taking fortunes for speeches from Wall Street horrors who almost totalled the global economy.

The core of seriousness isn’t a grim countenance or a portentous tone. It is a philosophy strongly held enough to endure however long it stays out of fashion. Thatcher had it. Blair did not.

Sanders has believed what he still believes since starting as a civil rights activist as a student. This seriousness, I think, is why young Democrats prefer him to Hillary by margins of up to 80 per cent. The young are generally dismissed as unserious, of course, but nothing could be more wrong. They see things with a crystal clarity which becomes obscured as the passing of the years makes hypocrites of us by tempting us to make accommodations with our principles. What the middle aged smugly know as naive idealism is the recognition of simple truth.

One simple truth battered home by Sanders is that US campaign financing is wickedly corrupt, with presidential candidates purchased by corporations or billionaires almost exactly as congressmen were bought by Don Corleone.

Donald Trump makes the same point. But, where that freak show grotesque is corporately funded (by himself), almost every cent of Sander’s funding is from tiny donations. He is in hock not to investment banks or Big Oil or some gruesome casino owner from Vegas, but to the tens of millions who gave him 10 bucks, and the tens of millions more for whom they stand proxy.

Another simple truth he voices is that America, like Britain, has become ever more economically unequal these recent decades. He may not have the solution (no one appears to have that), but he offers the analysis with integrity and authenticity. When Hillary talks about fairness, she is palpably paying lip service to ideals she regards as childishly utopian.

The nose-holding case for her to become President contends that at this supremely volatile and menacing moment in history, the planet’s paramount need is for her foreign policy experience.

I find this argument depressingly persuasive. And yet, buried alive beneath the layers of mid-life flab, I still hear the faint echo of a young man who felt and thought things with unsullied passion because those things were right.

The purity of political belief generally fades with time, which is why we become less serious as we age. So give thanks for an eternally young 75 year old with the brogue to transport you to the Carnegie Deli table next to Jackie Mason’s, and with beliefs that are wholly impervious to the erosive power of time.

Even if Bernie Sanders wouldn’t make a great leader (the precedent set by Jeremy Corbyn, his closest British equivalent, is not encouraging), he makes me wish I was 20 once again; and gazing beatifically at him through tear-sodden eyes on the night he concedes the nomination to a poster girl for principles suppresed and ideals trampled underfoot on the long forced march to power.