"It is a new evening, is it not?" To paraphrase Tony Blair. Last night, after Gordon Brown's resignation, we saw David Cameron driving to the Palace straight into a meteorological metaphor. After a long, patchy afternoon and a dull evening, the sun suddenly came out in that way it can, and flooded the scene from behind. A rainbow appeared.

A rainbow! On cue! Ready when you are Mr de Mille! A rainbow appeared behind Buckingham Palace saying that a higher authority had agreed a covenant with the British people that never again would... you should complete that sentence in your own time. And then a heavenly chorus swelled slowly and (no, hang on, that can't be right). What had happened?

Gordon Brown had resigned in a full and final settlement. Initially it was possible to scan it for wriggle room. "I've informed the Queen's Private Secretary that it's my intention to tender my resignation." There are two soft steps in that sentence. Blair could have turned into a 10-year mandate for government. "In the event the Queen accepts" – that's another one. The Queen might argue him out of it, in the national interest, for the sake of global stability and the young mother I met in Harrogate...

Ah, but then Brown was wishing the next prime minister well. Wishing him well. That was the end, then. That was straight. That was a very decent thing to say. It wasn't true, looking back on it, but it was well said.

"Only those who have held the office of Prime Minister can understand..." he went on. Now that was true. It's like the old maxim: "It doesn't matter whom you marry because it always turns out to be someone else." It's the problem of power. You start like a fresh-faced idealist with generous hair and you end up, quite suddenly, with a tortoise-like head and neck pushing out of your collar (Tony Blair, you must have noticed).

"I have been privileged to learn about the best in human nature and much about its frailties, including myself," he said, smiling in the right place.

Admirers of Gordon Brown (who will have multiplied overnight) will scourge the cynical for saying things like this. But if Gordon will write a proper book about the frailties in himself which his premiership has exposed he will deserve a place in heaven.

"Thank you and goodbye." That was an odd ending to a well-received speech, He's only going up the road, after all. I'm sure we'll see more of him. It isn't... the end of the world. It isn't the Apocalypse.

His lot will be back soon enough, no doubt, let's not make a crisis out of a drama.

Then, Cameron. Good Lord. The amateurs won after all. They beat the professionals. His speech outside the Downing St door made his pitch. The elderly, frail, vulnerable. Bit of freedom and fairness. The Tory-hating section of society will have climaxed in their loathing at these words. Personally, from my occasional encounters with him, dating from 2001, Cameron has always seemed a decent, public-spirited, one-Nation sort of Tory who has been bred in the Treasury.

Then there was the husbandly touch around his wife's mid-section – it's an ambiguous area when your wife is pregnant – it became a little uncertain, and therefore the object of comment. Oh, it's a new day all right.

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