All organic matter is rotted by time. Bread grows mouldy. Cheese becomes stinky. Bananas turn black. Leaders go the same way. Decay is a fact of power. Prime ministers run out of ideas and road. They become exhausted and voters weary of their governments. Broken promises, internal contradictions and accumulated enemies catch up with all but the very luckiest. Elements of a prime minister’s character that were applauded as virtues when they first took office are attacked as vices when they approach the end.

So the unusual thing about this government is not that it is decaying. The distinguishing feature is the rapidity of the rot. Theresa May has been prime minister for less than 16 months, but her government already has the reek of camembert that has been at the back of the fridge for too long.

How strange it is to reflect that her party made her prime minister because it thought a government led by her would be boringly dependable. They thought they were commissioning a leader who would give them grey but competent. Instead, they have got government as rolling tragicomedy.

In barely more than a week, we have seen the removal of two cabinet ministers and a clamour for the head of a third. The defence secretary has had his stripes torn off because of his conduct towards women. The international development secretary has been sacked for running a covert freelance foreign policy while in one of the most sensitive areas of the world, then pretending that she hadn’t, then having to admit that she had when previous statements were shown to be false. The actual foreign secretary is only just clinging to his once great office after endangering the liberty of a British citizen imprisoned in Iran and then refusing to give a proper apology for this atrocious blunder.

Even by the baroque standards of this administration, that is quite a triple whammy. There may be more to come. Shivers of fear ripple through Number 10 that there will be further revelations about other ministers while they nervously await the outcome of continuing investigations of the conduct of people who are still, for the moment at least, members of the government. All of which makes Mrs May’s now inoperative election rhetoric about being “strong and stable” look more risible by the day.

People can be heard asking: has there ever been a more chaotic government? I have been around long enough to remember that similar levels of mayhem have erupted around previous prime ministers, including some of the strongest ones. It happened to Tony Blair. It happened under Margaret Thatcher. What makes this period seem especially anarchic is that there is no apparent theme to the turmoil. No one has left the cabinet over a burning issue of high principle. The great question of the hour and the most demanding challenge for this government is Brexit. When Mrs May arrived at Number 10, it was widely assumed that the divisions over Brexit would be the cause of dismissals and the trigger for walk-outs from her cabinet as they split about which course to take. As it turns out, no minister has yet quit over Brexit, though that may well come when the government finally confronts the crunchiest decisions about Britain’s future relationship with the EU and how much it is willing to pay for the divorce settlement.

The Fallon and Patel dismissals and the demands for a Johnson sacking have nothing to do with Brexit. They do not seem to have anything in common at all. Except one thing. The binding theme is that they have all happened under Mrs May. This raises a big question that is central to her colleagues’ calculations about whether she, too, should be fired. How much is she to blame?

Whenever a minister is swirled by scandal, you can always argue that fault lies with the prime minister on the grounds that he or she shouldn’t have had the miscreant in their government in the first place. This is, it seems to me, an unreasonably harsh benchmark. It would make it impossible for any prime minister to form a government if he or she were restricted to appointing only people who could be guaranteed to be peerlessly competent and impeccably pure at all times. I’m afraid the voters don’t send enough saints to parliament for that to be a practical rule.

Sir Michael Fallon was a minister whom Mrs May inherited from David Cameron. It doesn’t seem fair to blame her for the former defence secretary’s past conduct towards women. I give her credit for showing him the door. The case of Priti Patel does raise issues about the prime minister’s judgment. Mrs May promoted her to international development, which was a surprise at the time, not least because Ms Patel had previously argued for the abolition of the department that she was tasked with leading. To many colleagues, it looked like an appointment based less on merit and evident qualification to do the job than Mrs May giving a seat in the cabinet to a right winger who was one of the prominent Leave campaigners in order to satisfy the hard Brexit tendency.

Facebook Twitter Pinterest ‘Ms Patel’s replacement by Penny Mordaunt is a further manifestation of the Brexit fault-line on cabinet-making.’ Photograph: Andy Rain/EPA

Ms Patel’s replacement by Penny Mordaunt is a further manifestation of the distorting effect of the Brexit fault-line on cabinet-making. Perhaps Ms Mordaunt will prove an outstanding performer in the post, but it wasn’t experience that secured it for her. She looks better qualified to have filled the vacancy at defence. There were other junior ministers more obviously suited for promotion to international development secretary, but they were ruled out because they were Remainers. Ms Patel was a Brexiter so had to be replaced by the Brexiter Ms Mordaunt to maintain the fragile balance of the cabinet. The gravest question about Mrs May’s judgment is her appointment of Boris Johnson to the Foreign Office. It was a surprise to everyone, not least himself, when she made him Britain’s face to the world. There was no love in that appointment. The prime minister can’t stand the man she made foreign secretary and it was not long after she elevated him that she made a rather vicious joke about having him put down like a dog when he had outlived his usefulness. The calculus at the time was that one of the senior offices of state had to go to a Brexiter and it would be better, in the famous expression of Lyndon Johnson, to have his namesake “pissing out of the tent”. I recall some commentators and many Tories hailing it as a May masterstroke; it doesn’t look so clever now.

There is a more general argument that this unruly government is so dysfunctional because Mrs May can’t get a grip on her colleagues. Ministers are flouting her authority, freelancing on policy and indulging in feuds with each other because she is too enfeebled to curb them. In the words of one former cabinet minister: “The basic problem is that we have a prime minister who is desperately weak.”

The answer, so say a lot of Tory MPs, is for Mrs May to conduct a sweeping reshuffle of her cabinet. It is contended that the way to stop the rot is to have a house-clean of the duds and the suspect. A radical reconfiguration of the senior team would both reassert her authority and allow her to bring on fresh, younger talent from the 2010 and 2015 election intakes who are untouched by scandal. For those pressing this course, it would have the added advantage that it might widen the potential pool of candidates when the time comes for the Conservative party to select a new leader.

When she called the snap election, Mrs May did plan to follow it with a major shake-up of the cabinet. But then she lost her majority and with it so much of her authority over colleagues. A major reshuffle in her reduced circumstances would be pregnant with peril for a precarious prime minister. The cautious side of her nature will be telling her – and it wouldn’t be entirely wrong – that a prime minister in such a brittle position can’t risk making any more enemies than she strictly has to. It seemed like a very good idea to her to replace Sir Michael Fallon by promoting Gavin Williamson from the whips’ office. The expletive-rich reaction to that appointment among furious Tory MPs is an illustration that you only make one friend when you promote someone while you create many foes.

There are also some warnings from history, the most pertinent being the example of Harold Macmillan. By 1962, mould was eating his Tory government, though it had taken more than five years for the rot to set in, rather than just 16 months. He responded with “the Night of the Long Knives” when he dismissed seven of his cabinet, a third of the total, and among them the chancellor. He conceived this as a gambit that would rejuvenate his government and demonstrate that he still had a grip. There was a furious backlash and more scandals followed. He was gone from Number 10, using illness as an excuse for his retirement, the following year.

It would be pretty risky and therefore out of character for Theresa May to conduct her own Night of the Long Knives. So it may be that what we have to look forward to is more Days of the Stinky Cheeses.