How dare the discredited party donors and fuddy-duddies who make up the Lords do anything other than pass the Article 50 Bill unamended?  Or so some of our fellow-Brexiteers ask this morning.  The question is a misunderstanding of how the constitution works (or should do).

The Upper House is a revising chamber.  In other words, its role is to take what the Commons send it, have a good look at it, tweak bits it doesn’t like – and send it back.

This is what it has decided to about the Bill to move Article 50 and the rights of EU nationals in Britain.  We think it is mistaken to slap an amendment on the face of the Bill, for reasons we have previously set out, though the view of the Government and the Lords on the issue itself will not be all that different, if at all.

What the Lords is not entitled to do, however, is defy the will of the lower House if the latter has a manifesto commitment behind what it sends – or, for that matter, the biggest-ever vote for anything in British history, in the form of last year’s referendum result.

And so it is in this case.  So if the Commons rejects this Lords amendment, as it should, and duly sends the Bill back to the Lords in its original form, peers should let the matter rest there.

Our sense is that they agree – and that Labour in the Lords, in particular, get the point.  What took place yesterday looks less like peers digging in for a fight than preparing, after a show of defiance, to run up the white flag.