David Cameron didn’t gain a majority in 2010 and is unlikely to win one next year.  That this is so has left him in a weak position from which to exert his authority over Conservative MPs and Cabinet colleagues – so much so that at times he has been unable to take decisions at all.  For example, last year’s reshuffle was postponed twice, the first time because of the volatility of the Parliamentary Party, the second time because of the interaction between its fractiousness and his mishandling of the Syria crisis.  Furthermore, he has a strong conciliatory streak: the Prime Minister’s natural inclination is to smooth over problems and difficulties – particularly if they are ones that may fret the Westminster Village but scarcely register with Britain’s voters.  When he was labelled “Willie Whitelaw with an iPod”, it was a comment on his character as well as his politics.

For this reason, the most likely outcome of the investigation that he ordered into the spat between Michael Gove and Theresa May was a Downing Street statement which said, in effect, that both regretted the row and promised not to repeat it.  Instead, Cameron has embarrassed the Education Secretary by insisting that he apologise, and infuriated the Home Secretary by insisting that Fiona Cunningham, one of her closest advisers, resigns.  It is like watching Whitelaw come on all Jean-Claude Van Damme.  What on earth has got hold of the Prime Minister?

Undoubtedly, he is irritated with the lack of discipline of his friend, the Education Secretary.  Downing Street admires his talents, but worries about his focus.  Gove has form in making audacious remarks to journalists at delicate times: remember his admission that he would vote to leave the EU were there to be a referendum then (and presumably now).  His zest for adventure can lead him on to other Ministers’ turf, as it did over the First World War commemorations.  And his loss of patience with the Liberal Democrats has been awkward for Number 10 – hence the semi-comic Times (£) article rushed out by the Education Secretary and David Laws, his junior Minister, over the former’s hostility to Nick Clegg’s vainglorious free school meals programme.

Unarguably, too, Cameron was angered by the action of Theresa May’s Special Adviser, Fiona Cunningham.  When wielding the knife on behalf of their bosses, SpAds usually try not to leave their fingerprints on the handle.  By posting a critical letter from May to Gove on the Home Office’s website, Cunningham was not just leaving those prints in place, but brandishing the bloody knife in public.  Cameron, a former Home Office SpAd himself, will have grasped at once that she was in flagrant breach of the code that governs their actions.

There is a case for arguing that the Prime Minister has called this one wrong.  The Education Secretary is on the verge of a showdown over an issue that could scarcely be more important – the vulnerability of Britain’s institutions and children to Islamist extremism.  He has led the intellectual opposition to it within the Party in opposition and government.  Whatever the rights and wrongs of his disagreement with Theresa May may be, this public climbdown weakens his position on the verge of a big moment.  Furthermore, the public view of the Government on counter-extremism is not the private view of Charles Farr, the head of the Office for Security and Counter-Terror.  The Gove apology buttresses the latter, and is thus unhelpful to a position which Number 10 itself had to fight to get.

And while Gove has been required to make an apology, May has been forced to lose a SpAd – and not just any old adviser.  Cunningham was one of the Home Secretary’s three closest office allies.  Losing her may or may not be a blow to May’s future leadership aspirations, but is certainly a disruption to the team which she relies on to keep a grip on the Home Office.  The Home Secretary is not a gregarious politician.  This trait runs side by side with a ferocious loyalty to the few people that she seems to trust.  She is unlikely to forget or forgive Cameron for forcing Cunningham’s departure.

But there is a more simple, straightforward way of viewing the Prime Minister’s response to a fracas which overshadowed one of the most important days in the political calendar – that of the Queen’s Speech.  The Education Secretary was indiscreet.  And the Home Secretary’s SpAd responded with what was in effect a declaration of war.  Collective responsibility must be upheld and open breaches of it punished: let one go, and a precedent has been set.  I read Cameron’s cracking of the whip as a sign of growing confidence.  The Conservatives won the Newark by-election.  The economy is growing and living standards are rising.  Ed Miliband’s position is weak.  This is not to argue that the Prime Minister’s buoyancy is right; merely to explain why it is there in the first place.

One more point.  What drove the Prime Minister most in making his decision, I suspect, was neither an exasperation with Gove’s quirks nor a fear of May’s ambitions.  Rather, it will have been a long-held view in Number 10 that SpAds shouldn’t be agents for the Ministers they serve, but servants of the Government as a whole.  Andy Coulson tried to enforce this view.  Craig Oliver, his successor, is known to hold it strongly. Neither May’s advisers and Gove’s former ones, Dominic Cummings and Henry de Zoete, have ever been fully signed up to it (to put it mildly).

Earlier in this Parliament, Cameron summoned SpADs to Downing Street.  “Who do you work for?” he asked them, individually. Each gave the name of his Minister.  All were then told by the Prime Minister that they were wrong.  They worked, he said, for him – that’s to say, for the Government as a whole.  Gove may sometimes exasperate Cameron, and May vex him, but his crackdown is aimed principally at neither.  He has Ministers’ special advisers in his sights.