Let me illustrate what I mean. On September 2, 2012 an article appeared under the Prime Minister's byline in the Mail on Sunday.  It began: "This week, politics starts again for the autumn and I profoundly believe we can face Britain's challenges with confidence." The word "challenges" is used by politicians to refer to problems which they have no idea how to tackle, or none which they are willing to share with a wider audience. The article also made profligate use of such terms as "vision", "truth" and "progress". It was characterised not just by intolerable banality but by a vacuous and self-regarding strain of moral uplift. Here is the ending:

At every turn we are taking the hard road over the easy path and we are doing so because we have a clear destination in mind: a truly great Britain; equal to the challenges of the 21st Century; a country we are proud to call home not just for this golden month of the Olympics and Paralympics but in every month, all the time.

I'm confident we're making progress. And I'm more ready than ever for the challenge ahead.

Fair-minded readers will say Mr Cameron should not be judged by an article which he certainly did not have time to write himself. I agree, but do not regard this as a full defence. For the article was the Prime Minister's opportunity to speak directly to readers of the Mail on Sunday, and he insulted them by showing not the slightest interest in doing so.

From the point of view of the No 10 machine, it was fine to submit a string of unreadable platitudes, because no normal person was expected to get through this stuff. The piece was aimed at correspondents who devote their lives to extracting stories from unpromising material. Simon Walters, the political editor of the Mail on Sunday, duly produced a front-page piece under the headline, "Cameron roars back: I'm no mouse".

The word "mouse" was not in the article. It had been supplied by Tim Yeo, a Tory backbencher, who had written some days earlier in an article in the Daily Telegraph that on the question of a third runway for Heathrow, Mr Cameron "must ask himself whether he is man or mouse". But the Prime Minister's assertion, somewhere in the depths of his piece, that it was time to "cut through the dither" (itself an abstract statement of questionable value) had provided sufficient evidence for Mr Walters to write his story, and for the rest of the media to get the message too.