Once he was the great white hope for government - or, at least, for enforcing the Michael Gove mission on education. Now, it seems, he’s suspected of “going native”, as Westminster terms it.

I’m talking of Her Majesty’s chief inspector of schools. Sir Michael Wilshaw talks tough, but recently he has appeared rather less sympathetic to the government.

No wonder education secretary Nicky Morgan reportedly reckons the next chief inspector, when Sir Michael retires later this year, should be more aligned with the government’s approach. Pundits suggest that she’s setting her sights on the US: the frontrunner is reckoned to be Dave Levin, co-founder of the KIPP charter school group, which set up a network of 183 high-performing schools. He’s frequently described as the “scourge of the unions”.

Sir Michael has himself been a scourge of heads and schools that (he feels) have let things slide and don’t pull students up on every slip in uniform and behaviour. Yet, though I’ve disagreed with many of his most hard-line statements, all must concede that he’s done the business himself, with spectacular success, in the toughest settings. He knows what must be done, and also appreciates that it takes time: hence this recent manifestation of increasing humanity, perhaps.

Time is the enemy of politicians, however. They’re in a hurry; impatient. I’ve occasionally spoken to ministers or their close advisers and discovered two statements guaranteed to lose their interest: “It’s not as simple as that” and “It will take time”. If Sir Michael is starting to show that measure of understanding, no wonder he’s falling out of favour in the Department for Education: and it’s suggested there’s no one in Britain able to take over the job - at least, no one in line with government thinking. So they’re thinking about going abroad.

Ministers in the past three administrations have spent time travelling the world, finding education systems that work. Finland was regarded as the shining example. More recently Shanghai and Korea (not the one with the nuclear weapons, the other one) were held up as the places that really know how to do maths, hard work and (don’t overlook this) that particular skill of teaching classes of 90 students and more (goodbye, teacher shortages).

I’m not just embarking on another rant about governments viciously enforcing their own agenda. But I don’t believe that someone, however successful in the US system, will necessarily understand how Britain works (the bad bits as well as the good). Moreover, an imposed approach imported from outside never works: I thought we all understood this by now.

My anxiety goes deeper than that: the danger was outlined by Eric Bolton. Remember him? I do, though I was a very young head when I heard him speak.

Eric Bolton was a senior HMI from 1983 to 1991, back in the days when we revered Her Majesty’s Inspectors. They would visit schools and make measured, considered judgements, offering wisdom and advice for improvement while also taking their notes back to headquarters so they could disseminate examples of excellence and of difficulty, and plan the solutions. There were no high-stakes inspections then: none of the simple pass-or-fail so beloved of ministers since those days. It was an inspectorate respected by the entire profession, and hugely influential.

In a letter to The Times last Monday, Eric Bolton described the function of inspection as being “to give professionally independent advice about the state of the education service”. If the remit has changed so as to be aligned with the government’s approach, as Morgan suggests, then every single educational goalpost in the country has been moved.

Of course it has. No government nowadays wants independent advice. Rather it requires its own prejudices and agendas to be reinforced and enforced by its own tightly controlled inspectorate.

I’ve always dubbed Ofsted the government’s Rottweiler: if ministers feel it’s lost its teeth as Sir Michael has mellowed, then to most of us it’s improved. But be warned. The next Rottweiler they import will come with extra-large fangs.

Dr Bernard Trafford is headteacher of Newcastle upon Tyne Royal Grammar School and a former chairman of the Headmasters’ and Headmistresses’ Conference. The views expressed here are personal. He tweets at @bernardtrafford

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