During the last Parliament, two posts of mine drew slightly miffed text messages from a Number 10 staffer. The first was my overview of David Cameron’s conference speeches, which discovered in them a problem that, I believed, bedevilled his leadership in general: an absence of consistency and conviction. The second was about what Cameron could learn from Ed Miliband: the presence of consistency and conviction.

I forget the exact wording of the text I received in response to that second post, but it was along the lines of: “I just thought it was funny when you claimed that DC isn’t consistent. But if you think that Miliband’s politics are like a stick of rock, I genuinely feel sorry for you.”

Well, pity me not. Cameron may have cruised to victory against Miliband in last year’s general election, but I still stand by what I wrote in those posts. Too often, the Tory leader would speak stirringly about a social ill – as he did about poverty in his conference speech of 2009 – and then never return to it again. Whereas, for all his flaws, the former Labour leader would hit on ideas such as the “squeezed middle” or “One Nation”, and then never stop returning to them. His motifs became themes.

Except, in this Parliament, with Miliband vanquished, something different seems to be happening. I noticed it most clearly earlier this week, when Cameron delivered a terrific speech on prison reform. But it was also there in his recent article for the Sunday Times (£) on the Establishment’s bias against ethnic minorities, and in a Times article (£) on the segregated existence of women in certain immigrant communities. “If you’re a young black man, you’re more likely to be in a prison cell than studying at a top university,” he observed in the first of these.

Not only are all these Prime Ministerial interventions consistent with each other – all to do with the social injustices that drag entire classes of people down – they are also consistent with his conference speech from last October. Some of that speech’s finest passages were about prisons…

“This is going to be a big area of social reform in the next five years.”

…institutional racism…

“One young black girl had to change her name to Elizabeth before she got any calls to interviews.”

…and gender inequality

“I’m a dad of two daughters – opportunity won’t mean anything to them if they grow up in a country where they get paid less because of their gender rather than how good they are at their work.”

Even those two words that Miliband tried to seize for himself – “One Nation” – are being seized right back. They appeared in that conference speech, and they have appeared in almost everything Cameron has said since.

You might be thinking: these are just words, give me action. But words can translate into action, particularly when they come from the mouth of a Prime Minister. If Cameron keeps on talking about social reform, then it suggests that that is where his priorities lie. And if that is where his priorities lie, then it is more likely to get done. This is a great joy for those, including me, who have been going on about prisons for years. There are worse people to have on your side than the utmost elected authority in the land.

And there are worse people for Michael Gove to have on his side, too. Who cares if Cameron is riding on the back of his Justice Secretary’s reforms? He neglected to do so when Gove was reforming schools during the last Parliament, and look what happened there: Gove ended up losing his job as Education Secretary, and his revolutionising zeal left with him. This time, there is no such reticence. The great changes that Gove is overseeing are sanctioned from on high.

All of this gives the Government a character that it would not have had otherwise. So much has been jettisoned since Cameron became Tory leader – the greenery, the NHS, the Big Society – that his leadership was beginning to lose all definition. It was almost as though the crown had been passed prematurely to George Osborne, who exercised his rule with the Northern Powerhouse and a National Living Wage and welfare cuts and… so on. Yet now? The Chancellor is still there, delivering on the prose of his latest Budget. Except he’s been joined by a Prime Minister who is bringing the poetry.

It’s a powerful combination. When David Cameron’s words have the twang of conviction about them, when he sticks at his themes until they stick in our minds, there are few more persuasive communicators in all British politics. The Conservative Party should be glad to have him back.

Which just leaves the question: why has this change come about now? Perhaps the Prime Minister has found something that he really does care about. Perhaps his impending departure has clarified his mind and driven him to action. Or perhaps, as I like to assure myself in my moments of self-doubt, that text-happy Number 10 staffer has realised the truth: that I was totally correct in the first place.