What a humiliating defection! What a shock to the system. What total and utter madness. What a humiliation for Labour that Quentin Davies should have joined the party.

All that sucking up from Gordon Brown . . . urgh. Just when you thought the next Prime Minister was planning how to take over and renew the Labour Party, to raise new Labour to new heights, lead it to victory at a fourth general election — there he was sitting down and tickling the underbelly of Mr Davies, one of the most abjectly unimpressive of a pretty abjectly unimpressive bunch of Tory MPs.

Here is the man who, in his only and brief frontbench position in 20 years as an MP, tried to break the Northern Ireland peace agreement, ending the bipartisan approach on the Province that had endured at Westminster for decades. Here is a man elected as an MP under Margaret Thatcher, who served in the Cabinet of Iain Duncan Smith, the most Eurosceptic Tory leader ever, who stood for re-election under William Hague and Michael Howard, and now claims a collapse of confidence in Conservatism under David Cameron — and then moves to the left, not the right! It is simply ridiculous.

Worse, it shows off the worst aspect of Westminster party politics, the bit that utterly turns off the electorate, makes it think they’re all the same and they treat it as just a game: ooh look, he switched sides! A decision of no consequence to the country whatsoever, based probably on some fit of pique and personal vanity, and some clever flattery from Mr Brown, is blown up into a momentous political move and the voters can see what nonsense it all is.

“I deeply disapprove of his whole attitude to politics, which is to put image-making first and to be entirely cynical about policy,” says Mr Davies of David Cameron. And he joins new Labour! Now I know we are post-Tony Blair and all that, but really: does Mr Davies think Mr Brown spent those new Labour years in opposition aghast at the spin and image-making that went on?

“You regularly (I think on a pre-arranged PR grid or timetable) make apparent policy statements which are then revealed to have no intended content at all.” Knock knock, Mr Davies, anyone been there for the past decade? Are you the only politician at Westminster not to know about the Downing Street “grid”? “You have displayed to the full both the vacuity and the cynicism of your favourite slogan, ‘Change to win’.” What does he think new Labour did? What does he think new Labour is?

“We the Labour Party must renew ourselves as the party of change”: that was Mr Brown at the weekend.

Good question, of course, what new Labour is — and today of all days, as Mr Brown takes hold of the reins from Mr Blair. The new Prime Minister has hardly set out a clear agenda for Britain in the past few weeks, smooth though his national tour has been. If Mr Davies is clear about Mr Brown’s policy on health and education and Europe and Iraq, then he’s one up on pretty much the entire Cabinet and certainly on the rest of the country.

No, Mr Davies’s decision — as is clear from his resignation letter — is personal. He doesn’t like the Cameroons. They have ignored him. Listen to the tones of anguish: “Ties of familiarity, of friendship, and above all of commitment to constituency supporters are for all of us very strong and incredibly difficult to break. But they cannot be the basis for living a lie . . .

“The last year has been a series of shocks and disappointments . . . You thus sometimes treat important subjects with the utmost frivolity. Examples are ‘inequality’ (the ‘Polly Toynbee’ moment — again you had a paper from me!), marriage and the tax system (even your own party chairman was unable to explain on the BBC what you really meant) and, most recently, mass consultation of the public on policy decisions. (In view of your complete failure to consult with anyone . . . on many of the matters I have touched on, or on many others, the latter was perhaps intended as a joke) . . .”

Failure to consult with anyone? Not Mr Davies by any chance? All those papers ignored . . . oh dear. This resignation may have had more to do with feeling snubbed than with anything else. In a sharp putdown when Mr Davies disagreed with something he said recently about a flat tax, George Osborne, the Conservative Shadow Chancellor and key Cameron ally, said: “Well, I’m afraid to say I actually disagree with almost everything Quentin Davies has ever said. I often find myself on the wrong side of the argument with him, even though we’re both Conservative MPs.”

This is more of a generational thing. The new, younger Tories leading the party do have a tendency to sound arrogant and patronising when they are arguing with older Conservatives, or sometimes radio interviewers, particularly when in a tight corner. It’s a kind of posh debating society thing — the sneering putdown.

So here we have a war of the generations, a politician railing at the end of his shelf life, the political equivalent of King Lear howling at the wind. And he sought refuge in Mr Brown, a man he felt he understood. Oh dear.

Mr Brown should have steered well away from this one. He only took the leadership on Sunday, promising that “I will endeavour to justify every day and in every act the trust you have placed in me”. Two days later he welcomes a lifelong Conservative and former Tory frontbencher into the Labour Party. Well, his members won’t be overwhelmingly delighted by that, that’s for sure.

It looks not just insincere but insecure in some way. It’s not as if Labour has a small majority, is fragile or needs to prove its inclusivity, is it? Or is it — and does it? Uh-oh.

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