Two things ought to be simultaneously possible when it comes to Nazanin Zaghari-Ratcliffe. First, that a woman who spent six years in an Iranian jail is perfectly entitled to be bitter about that and does not owe the Government a performative display of gratitude. Second, that she is not best placed to impartially judge the UK’s hostage policy.

Alas, partisans on both sides (which invites the question ‘sides of what?’; I suppose the many-fronted culture wars) seem to be stumbling at this unimposing fence.

This won’t matter if Zaghari-Ratcliffe returns to private life. But should she decide to campaign for changes to British policy – and her comments about not being free until everybody is out of Iran suggests she might – we’re all going to have to get better at threading this particular needle. Victims deserve sympathy, not carte blanche to demand political change.

In fairness, in some ways the Government has all but invited such a campaign. The decision to pay the £400m price tag for Zaghari-Ratcliffe’s release lends weight to her argument. If it was right to pay it, then surely there is a strong case that it should have been paid six years ago. What benefit, if any, was secured by the delay?

Whether or not it was right to pay, however, is another question. Whilst lawyers will zero in on the fact that this was technically a debt, not a ransom, there is no wriggling round the fact that a British citizen was held to ransom to secure the money. Across the world, the cost-benefit calculation on snatching a British national has just shifted hundreds of millions of pounds in the wrong direction.

(In any event, the debt was incurred to the Shah of Iran, who purchased tanks we rightly did not deliver after the monarchy was violently toppled by religious fundamentalists. The prospect of handing the cash straight to the ayatollahs is not a compelling one.)

Iran, as Robert Jenrick outlined last week, is a dangerous and belligerent regional power. It harbours an increasingly advanced nuclear programme and sponsors terrorist proxies across the region and overseas. We don’t know exactly what Tehran is going to spend a £400m windfall on, but it isn’t going to be good.

Now come the inevitable demands for an inquiry. There is an obvious danger that it simply becomes a stick with which to beat the Government, with ‘Why didn’t you do what Nazanin said?’ as its frame of reference.

This should not be allowed to happen, because an impartial inquiry into how this decision was made could be genuinely interesting. The UK has had a consistent line on this debt since 1979, right through the Thatcher years and New Labour. It held out for six years even after Zaghari-Ratcliffe’s kidnapping. Paying up could but British citizens overseas at risk. It would be good to know what changed the Government’s mind.