A little girl is supposed to have pointed to a famous figure and asked her mother: "What is that gentleman for?" Numerous names have been suggested over the years, including Evelyn Waugh and Charles James Fox. More recently, political journalists have taken to asking what the Liberal Democrats are for.

The sensible course to follow is for them to repeat the lines of the soldiers' song from the First World War: "We're Here Because We're Here Because We're Here". No further justification is surely needed.

After all, the old Liberal Party might quite easily have gone out of existence. Throughout most of the 1950s, its parliamentary strength was down to six, and at the 1970 election the figure was the same after a small rise in the intervening period. I do not want to weary the reader with figures, but there have been two periods of later expansion.

The first spell occurred with the formation of the Liberal-SDP alliance, when the new grouping had 23 MPs. The two parties merged in 1988 to form the Social and Liberal Democrats, though next year the "Social" bit was dropped to make the title snappier.

It may be remembered that Dr David Owen refused to join in the fun and carried on as leader of the independent SDP in which forlorn enterprise he was loyally assisted by the indefatigable Ms Polly Toynbee. The new party's first leader was Paddy Ashdown; at the 1997 dissolution it had 26 MPs, a progression steady but unspectacular.

The second spell – the jump – came with the election of a Labour government and 46 Liberal Democrat MPs. With the election after that, there were 52 of them. There are now 63 – four more than there were when David Lloyd George led the party at the 1929 election. More recent leaders such as Clement Davies, Joe Grimond and Jeremy Thorpe (who has largely been written out of Liberal history) would have looked out in amazement on the present sunny scene.

To read the leading articles in the papers, you would not think so for a moment. To listen to Liberal Democrat MPs discoursing on Newsnight and other places, you might arrive at the same conclusion. The Lib Dems hardly go out of their way to help themselves.

Mr Nick Clegg and Mr Chris Huhne are perfectly presentable candidates to become leader. Indeed, they are both of them perhaps a shade too presentable. In former times, political leaders used to go out of their way to cultivate eccentricities which made them recognisable and, in particular, appealed to the cartoonists.

Thus Lloyd George had his long hair and his cloaks; Winston Churchill his hats, his cigars and his array of ridiculous uniforms; Harold Wilson, his Gannex mac and his pipe, though he preferred to smoke cigars in the privacy of No 10. With modern or post-modern politics, the trick is not to draw attention to oneself and to avoid causing offence.

Sir Menzies Campbell caused offence not only by being old, or fairly old, but by seeming to be so. He had made a remarkable recovery from cancer, which must have taken a lot out of him. In another age he would have been praised for his courage, tribute paid to his physical stamina and mental strength; instead of which there were a whole succession of depreciatory references to his age.

Whether Sir Ming would have carried on – or wanted to carry on – to 2009 or 2010 is debatable. This year, but before the speculation about an autumn election got out of hand, he talked about serving a whole term; just as Mr Tony Blair had done earlier. It was the non-calling of the election that brought about the doubts concerning the leader: or, rather, it concentrated those doubts. So Mr Gordon Brown has not only ruined his own reputation (though it may yet recover) but done for the leader of the Liberal Democrats as well.

My own view, perhaps prejudiced, is that the Lib Dems should have stuck with Mr Charles Kennedy from the beginning. The part which Sir Ming played in the fall of Mr Kennedy is still mysterious; so, likewise, is Mr Huhne's part or that of his backers, in the departure of Sir Ming.

He has been appalling treated, not least by the press. Normally, I tend to come to the defence of my colleagues in the trade or profession. In column after column, for instance, I praise the accuracy of Mr Andrew Gilligan's reporting in the case of the dodgy dossiers, long before it became fashionable or even moderately acceptable to do so. But with Sir Ming and the press, there really was no excuse.

In the most recent by-elections, the newspapers uniformly proclaimed that Labour had done marvellously, the Liberal Democrats modestly and the Conservatives appallingly. In reality the Liberal Democrats had performed well, the Conservatives moderately well and Labour not well at all.

In the House, Sir Ming's slightest slip was seized on by the parliamentary sketchwriters as if they too were part of the conspiracy (which, of course, it is) between the backbenchers of the two big parties.

There is Iraq as well. The received wisdom among the political editors is that the question is receding in the public memory, if it has not vanished entirely. How true, how very true, their colleagues nod in sage agreement. One columnist who did not agree was my colleague Adrian Hamilton in last Thursday's Independent, and I agree with Mr Hamilton.

How could Iraq be receding, with casualty lists being read out at the beginning of Prime Minister's Questions? Nor should the public effect of military funerals be forgotten. In earlier periods, casualties of war were buried in foreign fields. Today, bodies are returned by air, if possible, and the funerals are often shown on television.

On television, virtually every night, bits of Iraq and of Iraqis are still being blown up. In any case the war and its consequences do not need the assistance of visual aids for them to be retained in the memory.

Sir Menzies deserves the greatest credit for speaking out against the war to begin with, when he was Mr Kennedy's foreign affairs spokesman, and later, when the results of the war were making themselves evident.

He has done a public service, equalling, perhaps exceeding those of W E Gladstone over the Bulgarian atrocities, Henry Campbell-Bannerman over the South African concentration camps and John Morley over the First World War. He is entitled to feel proud of himself.

In one area only has Sir Ming made a mistake. It was certainly a puzzling episode. At his spring conference in Perth he listed half-a-dozen topics as the price to Labour of Lib Dem co-operation. The most memorable of these was the scrapping of identity cards. Fortunately, no one took much notice at the time. Mr Clegg or Mr Huhne may, as the election approaches, have to take a closer interest in these matters, whether Sir Ming's successor likes it or not.