Imagine if the reverse had happened, if a Western media organisation had its bank accounts shut down, without explanation, in Russia, by a bank part-owned by the government.

Of course, the Kremlin has done far, far worse to domestic media it didn't like, and to journalists who needled or investigated it.

But the point is, we're supposed to be better. We're supposed to tolerate alternative points of view, even the hopelessly biased and often blatantly propagandist views regularly published on RT.

RT is a favoured media source for UKIP and the nuttier kind of Trump supporters. It indulges in conspiracy theories, it likes only a particular kind of commentator.

It manufactures a bubble within which (for example) Putin can do no wrong, and MH17 was brought down by just about anything apart from what all the evidence points to.

It seems to delight in taking a perverse position on Western establishment's 'received wisdom'.

It can be frustrating, absurd, and just plain wrong.

It is clearly funded by the Kremlin in order to inject a pro-Russian narrative into the English-language media, and greenhouse the kind of nonsense that bubbles under much of the 'alt-right' blogosphere.

But it can also be a useful gadfly, presenting the best – as well as the worst – of the counter arguments to the political status quo.

To attempt to shut it down would be an error with totalitarian echoes.

We do not yet know why NatWest took this decision. I asked, and they declined to say.

It could be that RT has done something, financially or otherwise, that entirely merits the cancelling of a banking service.

It could be that NatWest has very good reasons to have taken this action, and is really frustrated that privacy laws prevent it from explaining itself.

Or it could be that they just didn't want this kind of customer, at a time when Cold War-like feelings are growing on the Eurasian continent.

The fact they have now promised to review the decision, in the face of outrage from Russia and from RT and a chorus of RT-friendly commentators, suggests NatWest is not quite as sure as all that it has made the right move.

Which suggests it was the wrong one.

Free speech has and will continue to have much better martyrs than RT, but that's kind of the point.