During his 16-month stint as chief whip, Williamson famously never lost a vote on government business, even after the 2017 snap election saw May lose her majority. Allies say he played a pivotal role in persuading the Democratic Unionist Party to back the Tories in a confidence and supply deal.

He was – and still is – often compared to Francis Urquhart, the scheming chief whip turned prime minister in Michael Dobbs’ House of Cards. Williamson played up to this caricature at last year’s Tory conference when he said he preferred the carrot to the stick: “It is amazing what can be achieved with a sharpened carrot.” One unimpressed government staffer told us: “I think Urquhart is more sophisticated.”

Yet his undeniable skills with people are still much praised by colleagues who say they admire him for the time he takes with service personnel on trips overseas. (One aide lamented how long-planned trip schedules have to be ripped up because he loves to chat.) He is someone who insists on making visitors tea and coffee and builds relationships with his foreign counterparts with lots of humour, according to allies.

Some inside the MoD, however, have privately raised concerns that although he gives the appearance of listening, he is not taking on board their advice for new ideas and policies – perhaps, they say, because he feels insecure and wants to prove he’s doing it in his own way.

He is also acutely aware that each of the armed services has its own agenda, and he is having to learn how to rise above the politics of the MoD itself. One former government adviser said: “You’re not sure who’s your friend and ally and who’s your foe internally – the military, especially the army, have a pretty sophisticated briefing operation and campaigning capability where they will go and independently seek out members of parliament and commentators and influencers to try and push their agenda, which is something which is difficult to handle.”

Williamson has told friends he was shocked at the funding pressures facing the MoD as soon as he took home his red box the first weekend after being appointed to the role. As well as securing more cash for the services, he wants to focus on modernisation and new technology to make sure Britain can respond to new threats. And he is keen to get more service personnel into schools, not only to inspire the next generation but also to make the armed forces more visible and relevant to communities across the country – which in turn could bolster his demands for more cash from the Treasury.

But, ever the ambitious politician, he still carves out time at the end of most weeks to travel around the country for Conservative party events. He spends weekends at home with his wife Joanne and their two daughters, where they share the house with a pet cat, and his parents’ cocker spaniel Bessie when they come and visit from Scarborough. When the children have gone to bed, he likes nothing more than curling up on the sofa with Game of Thrones – that twisted tale of power games and back-stabbing.