The foreign secretary Jeremy Hunt has created a new role of ambassador for human rights, which, according to a Foreign Office statement, “demonstrates the UK’s commitment to defending human rights globally”. Plainly it does nothing of the sort. What it demonstrates is the government’s desperation to repair the reputational damage incurred as its support for the worst human rights abusers of the Middle East comes under increasing scrutiny.

Consider a few dramatic episodes in the past year, from Israel’s massacring of unarmed civilians in Gaza, to the murder and dismemberment of the Saudi journalist Jamal Khashoggi, to the carnage caused by the Saudi-UAE assault on Yemen. In each case, Hunt has performed his now familiar impersonation of an innocent bystander, expressing his “concern” while arms sales and diplomatic support to the culprits continue uninterrupted. In Yemen, substantial British and American assistance has been indispensable in sustaining a Saudi-UAE war effort that is the primary cause of the world’s worst humanitarian catastrophe, with an estimated 85,000 children under five dead from starvation or preventable disease, and thousands more killed in indiscriminate bombing.

To say that Britain lacks the credibility to promote human rights to others would be to state the case very gently indeed. But absurd as the creation of this new ambassadorial role undoubtedly appears, we need to go beyond the obvious accusation of hypocrisy, and take a closer look at the precise role of human rights abuses in UK foreign relations. Those abuses are not aberrational – deviations from our national “values” – but an established component of British power in the world.

From the days of empire right up to the present, Britain has worked to incorporate the global south into the world system on terms that benefit British investors and corporations, and which enhance the international power of the British state. For centuries this was achieved through the direct violence of colonial rule, but that became harder to sustain as Britain weakened economically and militarily, and as anti-colonial resistance grew more effective. The challenge was then to retain as much as possible of Britain’s unequal and exploitative relationship with the south, even as empire withered away.

This was achieved partly by supporting the United States as the new manager of the global system, and partly by supporting autocratic elites in the south wherever they could be relied upon to keep their states plugged into that system on the right terms, and to crush any domestic challenges to the status quo. These are the roots of Britain’s decades-long support for, and arming of, several violently repressive regimes, a consistent policy of both Labour and Conservative governments.

Naturally, human beings find it hard to engage in such behaviours while looking themselves squarely in the face, and so our governing elite has worked hard to convince itself and others that British power is a historical agent of modernity and enlightenment. Not a systematic denier of human rights, but a progressive champion of them.

As former foreign secretary David Miliband put it, “If the world is increasingly divided between firefighters and arsonists, then Britain has for centuries been a firefighter,” solving the world’s problems and promoting decent values. Tell that to the peoples of India, Iraq or Yemen, you might say. But Hunt’s creation of a new human rights ambassador is not for their benefit, but for ours, designed to shore up a narrative that bathes British power in the soft glow of innocence and nobility.

The dissonance between reality and self-image can sometimes be hard to reconcile, but there are ways to square the circle. British self-satisfaction has developed in symbiosis with a derogatory and often racist view of others, which can then be used to justify how those others are treated. Ministers frequently attribute the persistence of authoritarianism in the Middle East to the region’s “culture”, neatly obscuring the decisive role that Britain has long played in buttressing the local regimes, rigging the region’s politics in their favour.

The appointment of a UK human rights ambassador only appears ridiculous if you take facts like these seriously, and forget that, within the dominant ideology, Britain is axiomatically a human rights champion while certain others are axiomatically in need of our guidance in these matters.

There is no reason why Britain cannot come to play a genuinely positive role on human rights. But that will require an honest reckoning with our history, and a fundamental transformation of our entire global posture. Cosmetic gimmicks and PR stunts will fool no one but ourselves.

• David Wearing is a specialist on UK foreign policy in Middle East