Leading article: Finished? Maybe. Should he be? No

It is a rule of newspaper campaigns that they should demand only things that are likely to happen anyway. The Independent on Sunday has wilfully disregarded that rule in its support for the Prime Minister. It is neither inevitable or right that Gordon Brown should lose the next election, but it is idle to deny that the simplistic Westminster story has a certain self-fulfilling quality.

For some months now, the opinion polls have reflected this narrative back to the Westminster village. It is true, also, that the electoral auguries are not good for Mr Brown. Boris Johnson's election as London Mayor was followed by the loss of the Crewe by-election, the first Tory gain since 1982. Then there was Labour's fifth place behind the BNP in Henley. And now Glasgow East.

In fact, if we could just break out of the dominant narrative for a moment, the SNP's victory in Glasgow should be in a separate category. Politics in Scotland has its own ecology. The vote in the by-election was partly a positive vote for Alex Salmond's SNP, which has carried all before it since forming a minority administration in the Scottish Parliament last year. And, to the extent that it was a negative vote, it was a vote against the Scottish Labour Party, a hollowed-out one-party fiefdom that has taken Scotland for granted for 50 years. Mr Brown shares a little of the responsibility for the rottenness of Scottish Labour, but that is rather different from his record as Prime Minister.

In addition, some of the reporting of the Glasgow by-election has been frankly silly. Applying a uniform 22.5 percentage point swing against Labour to all Scottish seats and declaring that only one Labour MP would survive is childish. In fact, the loss of Glasgow East was particularly capricious and bad luck. It is still not clear why David Marshall, the former Labour member, should have resigned, despite senior ministers being deputed to try to find out.

Of course, Mr Brown has brought some of his wider problems upon himself, in particular the abolition of the 10p tax rate and the decision not to hold an election, as well as some other presentational snaggles. But he has been dogged by bad luck and unfairness, too.

As we have said before – and this is the nub of the matter – Mr Brown has not been a bad Prime Minister. Measured against John Major, the recent benchmark of mediocrity, even a SATs marker would give Brown a higher grade. In the past week alone, the Prime Minister has delivered two speeches of substance, which in a sane world should have been widely applauded. In Israel, he gave the Knesset a message of uncompromising solidarity balanced by a forceful condemnation of illegal settlements and the wall. At Lambeth Palace, he was eloquent in urging religious leaders to hold political leaders, including him, to account over global poverty. In strong language for a politician, he said European countries should be "ashamed" of farm subsidies that hurt the poor.

Yet the attention of the world's media, including this country's, was turned to a speech delivered in Berlin by Barack Obama that was uplifting and symbolic, to be sure, but where was the beef? Stripped of its context, the text was a disappointing compilation of platitudes and clichés.

Senator Obama's visit to London yesterday pointed up a paradox of modern politics. Mr Brown, a leader of substance, sought to borrow some of the popularity of the favourite to be the next President of the US, a leader of style. Senator Obama's news conference was largely content-free, but, probably tired, he spoke slowly so he sounded wise; he has an attractive cadence and a natural wit (the highlight of his trip? "Standing in front of No 10 talking to the British media").

He was gracious about Mr Brown's condition: "You're always more popular before you're actually in charge. Once you're responsible then you're going to make some people unhappy." And he offered him this solace: "There have been months when I'm a genius and months when I'm an idiot, if you read the newspapers."

Do not get us wrong. There is much about Senator Obama to admire. This newspaper supports him on Iraq and on talking to America's enemies. But there ought to be, surely, more respect for politicians with a solid record of government.

Even as we accept that Mr Brown's prospects look bleak, although not yet irrecoverable, we think that a shame. And we urge Labour MPs to think carefully about whether it would be right to depose a leader of such experience, judgement and seriousness of purpose.

What does it say about our political culture that Mr Brown should be judged so harshly by comparison with plausible showmen such as David Cameron and Senator Obama who, as the latter said, are not "responsible" and therefore have not had to take any difficult decisions?