What a pity the American ambassador, Woody Johnson, who watched Prime Minister’s Questions from the Gallery, did not stay for the subsequent business, when Sir Oliver Letwin defended our ancient liberties while taking numerous objections to his plan for indicative votes, and Andrea Leadsom, the Leader of the House, refused to take any interventions at all.

Even by her own high standard of cloth-eared rudeness, Leadsom’s behaviour was atrocious. Kenneth Clarke rose during her speech. He had just made a number of short, lucid interventions while Letwin was speaking.

Letwin had remarked that Clarke is not only Father of the House, having belonged to it since 1970, but a former Chancellor of the Exchequer and Lord Chancellor, to name but two of his Cabinet offices, so could cast more light than anyone else present on whether anything like today’s seizure by the Commons of control of the Order Paper has taken place within living memory.

When a great constitutional question is about to be decided, and when the Prime Minister is attempting (as every Conservative leader since 1846 has somehow managed to do) to preserve her party intact, it would evidently be courteous to hear what Clarke has to say, and it would without doubt be prudent too.

Leadsom entered the Commons in 2010 and before becoming Leader of the House served for 11 months as Environment Secretary. Here too are reasons why she might think it reasonable to take interventions from those who have served for longer.

And she must have noticed how Jeremy Corbyn’s refusal, the other day, to take interventions, made him look rude, weak, touchy, defensive, and impervious to any argument with which he happens to disagree, especially when made from his side of the House. Corbyn’s behaviour has prompted a number of Labour backbenchers to resign from his party.

Leadsom would not take Clarke’s intervention. She would not take any interventions. This was unbelievably stupid of her as well as unbelievably rude. It made her look like the representative of a Government which still has no intention of engaging with what MPs think, and just wants them to do as they are told.

She was followed by Valerie Vaz, the Shadow Leader of the House, who naturally allowed Clarke to intervene. He proceeded to remark that the Prime Minister had said the Government would allow time for indicative votes, and had this happened, the Letwin initiative would not have been required, a point Letwin confirmed by nodding.

In the course of his own speech, Letwin confirmed that he intends to vote for the Government’s Brexit deal however often it comes back to the Commons, and repeated his claim that he is not a revolutionary.

This is true, except that British and American revolutionaries often declare themselves to be conservatives, who in 1688 and 1776 were intent on preserving ancient liberties against an overweening executive.

Letwin’s tone was polite, friendly, well-informed, consensual, self-mocking. Unlike Leadsom, he wanted to make it as easy as he could for MPs from both sides of the House to agree with him.

He took interventions from John Redwood, Peter Bone, Jacob Rees-Mogg and a number of other Eurosceptics who profoundly disagree with him.

In exchanges with Rees-Mogg, he touched on the origins of Parliament, and its insistence on its right to control its own proceedings. The Commons asserted in the 17th century  “that in the end sovereignty lies here and not in Whitehall”.

Letwin added that “the official mind” finds this point impossible to grasp. He referred to “a very senior official” who had remarked that we are now in a situation where it is “necessary for Whitehall to save Parliament from itself”.

He was too charitable to suggest that Theresa May has an instinctive sympathy with “the official mind”. Her own mind is of that type. So too is Leadsom’s.

When they appear in the Commons, May and Leadsom sound like enemies rather than defenders of our ancient liberties, which is one reason why they now find themselves so disconcerted by Letwin’s conservative revolution.