Leading article: The end was messy. But a bigger fight lies ahead

Charles Kennedy should have gone before Christmas. Not because he is an alcoholic, but because he was no longer the right person to lead the Liberal Democrats. To be brutal, his alcoholism is part of that - but only because he was still in denial about it. He has not yet come to terms with his "drink problem", as he preferred to call it. At each stage, he has done something about it only when forced to do so. He sought medical help 18 months ago not because he accepted that he had a personal problem but because his senior colleagues threatened to resign if he did not. He made his public confession on Thursday not because he chose to but because his colleagues had lost patience and told a journalist about his treatment. As his former friend and campaign manager Matthew Taylor, MP for Truro, made clear yesterday, his friends have been trying for years to make him face up to his addiction. His response, all too familiar to those who know alcoholics, has always been to promise to do something about it and then to lapse again.

Looking back, what is surprising is not how much plotting there was against him and how much disloyalty his colleagues showed him, but how little. Again and again, they gave him the chance to deal with his problem without the public humiliation that he is now enduring. Last week, he unnecessarily prolonged the agony, thinking that he could tough it out and appeal over the heads of his MPs to a more sympathetic grass-roots membership. No doubt messages of support and sympathy were arriving in Mr Kennedy's office - the Liberal Democrats are, after all, the nice party. But it became undeniable yesterday that they did not reflect the mood of the party or the general public.

This is not because Liberal Democrats or the wider electorate have a censorious attitude towards drink. Britain is, in many ways, a nation with a drink problem. Fighting, puking, urinating and comatose young people are only the most visible signs of the country's troubled relationship with alcohol. Many workplaces conceal a quieter subculture of alcohol dependency. Yet the problems of addiction are better understood than ever before, and attitudes are generally non-judgemental. Although alcoholism may be more common in politics than in many other fields of human endeavour, it is possible for people who have, in the modern euphemism, "issues" with drink to excel in it. John Smith and Robin Cook were heavy drinkers, while John Reid and Alastair Campbell are dry. Mr Kennedy cannot complain that he has not been given a fair chance.

Nor has Mr Kennedy been a bad leader of his party. In such a tragedy - to use the word, for once, in its original sense of a hero brought down by a character flaw - it is easy to lose sight of his achievements. In 1999, Mr Kennedy was the right choice. His collegiate style held the party together and allowed it to pursue a twin strategy of focusing on a few distinctive issues nationally and on an ever-growing number of target seats locally. Under his leadership the party increased its share of the vote and its number of seats both in 2001 and 2005. It now has such a large bloc of MPs that a hung parliament is likelier than ever.

Mr Kennedy is right to claim credit for his sound judgement. He deserves praise for standing firm across the board on human rights, from asylum-seekers to Guantanamo Bay and culminating in the Government's defeat in November on its plan for 90-day detention without charge. Above all, he got the big decision right, on the Iraq war, even if the heavy lifting in terms of making the detailed case against the Government, day by day, channel by channel, was usually left to Sir Menzies Campbell. It is no coincidence that Sir Menzies is now the front runner to succeed him.

However, now the Liberal Democrats have the opportunity to have an open debate about their future. The Conservatives have just demonstrated how a leadership election can be a chance to engage public interest. It is the only time that all the leading members of a party can contribute to a free-ranging debate unconstrained by the rules of collective responsibility. This is precisely the time when the Liberal Democrats need to have that discussion. Whatever its detractors say, the values of the party remain distinct and well established in the public mind. It is the party of civil liberties, of social justice, of forward-looking engagement with Europe and of an ethical, rules-based foreign policy. Those are, as we noted at the last election, the values closest to those espoused by The Independent on Sunday.

We have come to the end of the Kennedy phase. The collegiate style had its uses, not least in papering over the division in the party between economic liberals and social democrats, pace Shirley Williams on the opposite page. But the values for which the party stands need to be promoted with vigour, creativity and clarity. Those are the tests that the party and the country need to apply in the leadership contest that will now take place. Nor is there any doubting the range of talent available among the 62 Liberal Democrat MPs that were returned to Westminster last May. As the Conservatives have shown, thankfully anything can happen in a leadership election. It would not help the party, or the country, for the Liberal Democrat leadership election to move to a swift and predictable conclusion. Politics has not been so interesting for a long time. With Tony Blair, Gordon Brown and David Cameron struggling so energetically for the slightly mythical centre ground, the Liberal Democrats need to fight harder than ever before. Let the debate begin.