No man is an island - Gordon Brown quoted John Donne in India last month - “and he was writing in defiance of a world and a time which had more reason to think of itself just as individuals pursuing their own ends. But as he suggested, in the world of 2008, our self-interest and our shared interest should be seen as one and the same.”

Sorry to plunge you straight into the turgid stuff.

Intimating that Donne was making suggestions about “the world of 2008”, meditating morbidly upon Alistair Darling and Northern Rock, seems stretching it to me, but I suppose you never know. Certainly an awful lot of things have come crashing home to land on Mr Brown's beach this week.

For the nationalisation of the Rock wasn't really about Mr Darling, or the competence of the Treasury. It wasn't really even about Northern Rock; most people are not unduly concerned about that - the bank had clearly become part of the public sector already, propped up by government subsidy, and the Conservatives' hysterical overreaction only made them look young and stupid. Public outrage will erupt if the Rock's shareholders are compensated, but only then.

So, no, Monday wasn't about any of those. It was about the Prime Minister, his Government, his character.

Mr Brown looked shattered on Monday. Not at the Downing Street press conference, but during Mr Darling's statement to the Commons, when the morning's make-up had presumably worn off and the Prime Minister, sitting next to the Chancellor, may have forgotten that the cameras were still trained on him. He looked as if he could barely keep his eyes open. Mind you, you could hardly see his eyes for the heavy black circles engulfing them. One of them twitched nervously, or angrily, or just tiredly. Whether or not it is true, as reported at the weekend, that Mr Brown is surviving on three hours' sleep a night, it is easy to believe. Even his own Communities Secretary, Hazel Blears, has publicly advised him to find some “balance” in his life: “a bit of fun as well as a bit of hard work”.

The easy badinage among the ministers surrounding him on the front bench on Monday never penetrated the Prime Minister's small black pod; it wouldn't have been able to find its way in.

No man is an island... For many months, the Prime Minister has been undermining his colleagues. The most obvious example was the cack-handed briefing from No 10 against a pro-European speech made by the Foreign Secretary, David Miliband, last November. But the Prime Minister is also a publicity thief. He steals announcements on security from the Home Secretary, Jacqui Smith, and allows his old mate Jack Straw to nick much of the rest of her brief. He swiped the announcement on using the private sector to get people off welfare and into work from the new Pensions Secretary last month. Watch him steal Ms Smith's thunder again today, overshadowing her Green Paper with a speech on citizenship.

When it isn't Mr Brown personally, it's his henchman and trainee PM, the Schools Secretary, Ed Balls, who muscles in on anything he can, from the drive against obesity unveiled by Alan Johnson last month (Mr Balls announced part of it a day earlier) to the new Culture Secretary's plan to introduce culture into schools.

Undermining his colleagues makes Mr Brown look small. A Prime Minister afraid of being surrounded by strong characters diminishes himself. A man unable to let others grow in stature only succeeds in making himself look petty and afraid.

Conversely, the way to succeed as prime minister is to foster strong characters around you. (Not necessarily as strong as Tony Blair allowed his Chancellor to be, but that's another argument.) I never thought I would say it, but listening to him interviewed on the radio this weekend, I found myself thinking how much we miss John Prescott.

No one has been more diminished than Mr Brown's Chancellor, forced to jump and bend to the will and whim of No 10 and then to account for their decisions. If Mr Darling is not big enough now to draw the flak from the Prime Minister, that is the Prime Minister's fault.

But the Chancellor is beginning to show signs of independence, letting it be known that he has had his disagreements with Mr Brown, and even suggesting in an interview at the weekend that any “robust exchanges” he has enjoyed with the Prime Minister are being saved for his memoirs. He looked a lot more relaxed than Mr Brown has this week. And other ministers - Alan Johnson at health, Mr Miliband, Mr Purnell - are beginning at last to make an impact in their own right.

In the meantime, the pieces of Northern Rock litter No 10. Move away from Westminster and hear what people think: that these are Mr Brown's chickens coming home to roost, a Chancellor and now Prime Minister who floated a public spending boom off the back of a greedy financial sector betting in increasingly convoluted structures not understood by politicians on rising house prices artificially inflated by foreign billionaires, the whole underpinned by ordinary people unprotected by a weak regulatory system put in place by the same man now intent upon using our money to prop up votes in his northern heartlands. Or something like that. Welcome to Britain, 2008: caustic, cynical, furious, and agog at the impotence of politicians in the face of the amoral, international super-rich.

As Mr Brown didn't quote the miserable Donne as continuing, never send to know for whom the bell tolls - it tolls for thee.

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