The home secretary is politically dead: long live the home secretary. Amber Rudd having sinned, and having in recent days performed her duty as a lightning rod for a perennially sinful prime minister, has been cast aside. Her successor will seek to draw the line on Windrush. The prime minister, as far as she is able, will huddle down in her safe room.

The basic narrative in this disturbing soap opera is so gripping and fast-moving that we risk missing the underlying themes and lessons.

One is that today, the cost-benefit analysis ratio of government changed. Rudd may claim to have known nothing about the migrant deportation targets – and if that is so, her own position damned her as unfit to do the job – but we know for sure that some officials in her department knew of the policy and the disproportionate effect it was having on black Britons of long-standing and positive contribution. Someone did the cost-benefit analysis and decided that the risk that the Windrush victims would be in a position to make a fuss, or that anyone would help them or listen to them, was outweighed by the benefit of making a government hurtling towards Brexit, with an immigration-fixated prime minister, look tough.



That calculation, having cost Rudd her job and any pretensions she may have had to lead her party, will now be revised. The Windrush victims did make a fuss, people – alerted by our own reporter Amelia Gentleman – did help them. And the public did listen. Today’s Commons debate was triggered by a protest petition that quickly amassed 100,000 signatures. In terms of community cohesion, this is good news. Not perhaps the unequivocal embrace of diverse Britain some would like, but a clear indication that an argument abut fairness, properly framed, can supersede even the post-Brexit vote hostility to difference. Whitehall might bear that in mind before embarking again on schemes to further disadvantage the disadvantaged.

Play Video 3:10 Windrush citizens: 'It's like having your world torn apart' – video

But now might also be a moment to think about how we got here. On the 25th anniversary of the death of Stephen Lawrence, it is worth pondering on what William Macpherson said in part two of his inquiry about institutional racism. It’s the most controversial element of his findings. People who like the rest, about dodgy coppers and vicious cowardly killers, tend to shy away from, or become hostile to, his warning that otherwise good people, unwittingly biased, can in their collective actions disadvantage and discriminate against people of colour. There is, I think, a deliberate misunderstanding from individuals and pundits who cry: “How dare you call me racist!” The then-commissioner of the Metropolitan police, Paul Condon, at the Lawrence inquiry itself, refused to accept the phenomenon might apply to his force. Just recently, one of the most senior officers in the Lawrence case again dismissed the idea of collective institutional bias as rubbish.

But to look at the Windrush scandal is to vividly see institutional racism at work. Theresa May, Rudd, Brandon Lewis, who admits he did know of the deportation targets, all the officials involved; they may be good people. They may have good intentions. They may, in part, be liberal in intent. But together they pursued and defended a policy that in its application, discriminated – not wholly but in large measure – against black Britons. Their lack of empathy or care at worst, lack of peripheral vision at best, resulted in what is pretty much a textbook example of institutional racism from the department that commissioned Macpherson in the first place.

Ministers rally round Theresa May after Amber Rudd resigns Read more

Given the convulsions, there will almost certainly be an inquiry into Windrush and by following the paper trail, we should pretty easily be able to find out exactly what has happened. But that will not be enough. Behind the scandal were questionable philosophies, assumptions and attitudes, and it is those we need to unearth.

• Hugh Muir is associate editor of Guardian Opinion