Priti Patel is a very lucky home secretary. Twenty-five years ago, when Michael Howard did her current job, the Conservative party lapped up his hardline penal policy of “three strikes and you’re out”. Patel shares much of Howard’s philosophy. But she is lucky his three strikes doctrine has gone. Patel would not be in her job if it applied.

In less than a week, three separate bullying charges have been lodged against Patel. The earliest, from when she was a junior minister at the Department for Work and Pensions in 2015, centres on a formal complaint of bullying and harassment. The second, from her time as international development secretary in 2017, involves what has been called a “tsunami of allegations” as well as “shocking” bullying of her own private secretary. The third, which came in her permanent secretary’s resignation statement, accuses her of creating fear by shouting, swearing, belittling, and making unreasonable and repeated demands.

In Cummings’s world, the loss of Patel would be both a victory for the hated Whitehall “blob” and for the hated BBC

In the not so distant past, all this would have meant curtains for Patel as home secretary. Ministers and senior officials have almost routinely had difficult relationships in the past. But they almost never resulted in career officials resigning. That’s because the expectation of robust private argument over policy is sensibly hardwired into the adviser-politician relationship from the start. For it to become personally intolerable is the unusual bit. For a minister to have triggered the very public resignation of one of Whitehall’s most senior officials makes Patel’s case unique.

Bullying in Whitehall and Westminster – and indeed more generally – was a high-profile issue during the previous parliament. The Tory party relentlessly attacked the former speaker John Bercow over alleged bullying of Commons staff. There must be “no bullying and no harassment”, wrote Boris Johnson in the August 2019 issue of the official ministerial code. Working relationships should be “proper and appropriate”, the code states. Bullying will “not be tolerated”. On Wednesday, the former Commons leader Andrea Leadsom told MPs that they must behave honourably “whatever the cost”.

Yet the cost of the bullying allegations to Patel has been very slight so far. On Monday, Michael Gove called her “a superb minister doing a great job”. Spurred on by the whips, Tory backbenchers rallied around Gove to praise the home secretary. One compared her to Margaret Thatcher by dubbing Patel “the current iron lady in the home office”. On Wednesday, with Patel sitting at his side in the Commons, Johnson insisted he was “sticking by” his minister. She was, he said, “doing an outstanding job”.

Johnson and Gove are smart enough, and have been around Conservative politics long enough, to know that praise of this kind for Patel is signally unmerited. Quite apart from the extremely serious allegations that she now has to answer, Patel is not a good minister, let alone an outstanding one. Her record is thin and so is her reputation. That Patel manages to combine arrogance with stupidity, a former colleague told me this week, is “toxic and terrible”.

So why is Patel still in place? It is not as if she is a particular favourite of the No 10 chief adviser, Dominic Cummings. But it may be that Cummings’s own almost pathological antagonism towards the civil service and the media means that events have forced him and Patel into becoming allies of convenience. In Cummings’s world, the loss of Patel would be both a victory for the hated Whitehall “blob” and also for the hated BBC, which has carried – with admirable fearlessness in the circumstances – two of the most damaging stories against Patel.

For that reason, some senior Tories argue, the issue for Johnson is really about timing. In this reading, the resignation of Sajid Javid as chancellor last month gives Patel a stay of execution. Johnson could not afford to lose two of his top three ministers so quickly, especially at a time when coronavirus allows him to pose as the unifying figure he would never be over Brexit. He is therefore boxed in, and dependent upon the report by his ministerial standards adviser, Alex Allan, into Patel’s behaviour. If Allan produces a damning verdict, Johnson can then decently decide that her position is no longer sustainable. Allan would help to deflect some of the criticism that would follow from Patel’s allies.

Priti Patel accused of bullying a third senior civil servant Read more

But the real reasons are surely political and ideological. Johnson feels he needs her. Patel’s presence in his government helps to preserve party unity on the contingent terms – they will become a bit clearer in next week’s budget – set by himself and Cummings. That fact is itself remarkable, since it shows both that the party is not, in fact, as united as it pretends, and also that Johnson’s 80-seat majority does not guarantee his control over the direction of the Conservative government as decisively as it may seem.

The Tory party may have settled its arguments over Brexit. But it has not settled its arguments over the state’s role in the economy and social policy. These debates have indeed now revived. Patel stands for an essentially Thatcherite approach. At the end of a decade in which David Cameron, Theresa May and Boris Johnson have all attempted, in their very different ways, to follow something they all called “one nation” policies, Patel continues instead to emulate Thatcher’s distinctive and divisive combination of liberal possessive individualism and authoritarian social policy.

Whatever she may think about it herself, Patel is no Thatcher. But Patel as home secretary has become one of the embodiments of the Tory right’s current capture of the party. She knows it, and so does Johnson. It is why she is still there, at least for now.

• Martin Kettle is a Guardian columnist.