Westminster chatter has been largely preoccupied with two men who have never held elected office but who continue to exert a special fascination: Dominic Cummings and Morgan McSweeney. Cummings was de facto chief of staff for Boris Johnson until he was sacked. McSweeney occupies the same role for Keir Starmer following the defenestration of Sue Gray, a former career civil servant and Whitehall fixer.

They come from different political traditions – Cummings is a libertarian, McSweeney a conservative social democrat - but they are both self-styled disruptors and restless for transformative change. They are both intolerant of the bloated administrative state, of what Cummings calls the “old permanent bureaucracy”, and loathe progressivism. Both are compelling speakers, fond of quoting from Sun Tzu’s The Art of War, and they share a certain single-minded fanaticism. They are simultaneously familiar to the public and mysterious; accountable and unaccountable.

In different ways, they both schemed to destroy elected party leaders. Cummings was so contemptuous of Johnson’s carelessness and incompetence as prime minister that, after he left 10 Downing Street, was intent on destroying him. “I orchestrated it [the partygate scandal] with a bunch of other people in Westminster who agreed with me that leaving him rattling around No 10 making a whole set of appalling decisions should be ended as soon as we could do,” Cummings told the Sunday Times on 9 February.

In his role as head of Labour Together, a network of MPs, intellectuals and wealthy donors which became a well-funded think tank, McSweeney knew that if Labour was ever to win power again the Corbynite left must be ruthlessly destroyed. The mission of Labour Together was a “deception without precedent in British politics”, according to Patrick Maguire and Gabriel Pogrund, co-authors of Get In: The Inside Story on the Rise of Starmer. That’s an exaggeration, of course. Labour Together had intellectual ambitions as well: to develop a politics of national renewal that could reflect the mood in the country in the bitter aftermath of the vote for Brexit.

It’s never wise for a special adviser to become the story but this happened to Cummings - whose defining role in the Vote Leave campaign was reimagined and recast in fiction by James Graham in the TV drama Brexit: The Uncivil War - and is now happening to McSweeney, the principal character of Get In. Through his work at Labour Together, then as head of Starmer’s leadership campaign and, later, the party’s election strategist, “the Irishman”, as Maguire and Pogrund call him, did more than any elected politician to create the conditions for Labour’s general election victory.

He remains in the shadows – he does not give interviews - but is discussed with hushed reverence at Westminster, even his most gnomic utterance studied for significance. Most pressingly, he understands that the task before Labour, an unpopular government without a coherent politics or sense of direction, is nothing less than to forge a new politics of the left in an increasingly anti-progressive era. After Trump’s crushing victory over the Democrats, the energy and momentum in the West is with the insurgent populist right. Even where they are out of power, as in Britain and Denmark, the populists are setting the terms of debate.

The politics of these times are comparable in many ways to the breakdown of the post-war settlement at the end of the 1970s, when the free market New Right rose and then consolidated its hold on power for nearly 20 years. The left did not understand what was happening because it was committed to old ways of thinking. Something similar is happening again but this time it is the populist right, not an exhausted and discredited Conservative Party, that is responding most deftly to the new, emerging political, cultural and economic realities. That senior Conservatives are discussing some kind of pact or merger with Nigel Farage’s anti-system Reform UK reveals the depth of their desperation. Why should Farage give ground to Kemi Badenoch’s dismal Conservatives? Far better, surely, to make them grovel. Cummings considers Badenoch to be a “useless dud” and the Tory party “intellectually dead”. He asks the right question of Reform: can they build and attract elite talent? At present, Reform is Farage and Farage is Reform. But who is Farage’s Cummings or McSweeney?

I have been reading a remarkable novel about a special adviser, The Wizard of the Kremlin by Giuliano Da Empoli. The principal narrator, Vadim Baranov, is a close aide, or “political technologist”, to Putin, whom he calls “the tsar” (he’s modelled on Vladislav Surkov, a longtime Kremlin adviser). Baranov has a background in theatre and believes that his role is to “direct reality”.

The book, a bestseller in France, covers the period from the chaotic, humiliating end of the Yeltsin regime to the eve of Putin’s full-scale invasion of Ukraine. It has a gallery of familiar characters: the oligarchs Boris Berezovsky and Mikhail Khodorkovsky, the warlord Yevgeny Prigozhin, and so on.

Above all it is a novel about power, about how it is acquired and used – power as the pure exercise of force. Working inside the government machine, Baranov, a cynical narcissist, knows he is powerful but that he is also dispensable. Real power, he understands, in the theatre of politics, lies not with the special advisor or chief of staff – with Surkov, or Cummings, or McSweeney - but with the tsar or leader. The question is: can they use it to effect the transformation they seek. Johnson couldn’t. Can Starmer? Or could he have arrived in power at precisely the wrong moment for his brand of progressive centre-left politics?