It turned out that Charles Kennedy can fight when his back is against the wall, after all. But it must be too late for him now. It may be unfair and a shame, but I do not see how he can pull off this last gamble. It is unfair, for example, to accuse him of dishonesty by denying that he had a drink problem before. People, even politicians and celebrities, are entitled to privacy and denial is hardly the most unexpected trait in an alcoholic. It is unfair, too, to blame him for the Liberal Democrats' strategic malaise when squeezed by a Conservative party that has at last realised the importance of fighting for the centre ground.
There will be many in his party and beyond who think that there was something admirable about his performance yesterday, and that his honesty, however belated and forced, should be rewarded. But the doubts crept through the carefully drafted words of the text to which the leader so visibly stuck.
He said that he believed "this issue is essentially resolved". That is, not completely resolved. He said that he had not had a drink for two months - a rather short period that may in any case have been subjected to some statistical rounding. And he conspicuously threw himself on the mercy of his party membership rather than that of his parliamentary colleagues.
Whether it is 11 or 12 of his front-bench colleagues that have signed a letter saying that they have no confidence in his leadership, Kennedy obviously does not think that he could win a vote of confidence among his MPs. That makes explicit what has been suspected for some months, that the Liberal Democrats are now in the unhappy position of being the first party since membership-democracy emerged in British politics (in the precursor Liberal Party) to face the problem of members and MPs facing different ways.
A few Liberal Democrat MPs may say yesterday's confession clears the air - it may have been the "tidying up exercise" that Andrew Stunell, the chief whip, trailed on the radio at lunch time. But it is hard to escape the conclusion that a majority of them would still prefer a different leader - especially as Kennedy seems to have reached it himself.
The threat to "do a John Major" has long been Kennedy's nuclear option, and yesterday he deployed it, but he may find that it is hollow. He has been popular among the grassroots members before and since they elected him to the leadership in 1999. Then, he won by only 28,000 votes to 22,000 in the run-off against Simon Hughes, the MP for Bermondsey who resembles an earnest vicar.
And the Major precedent was always dangerously different from Kennedy's situation. Major threw down the gauntlet to his own MPs in a contest that was over in a matter of days - having secured the support of his real rival, Michael Heseltine. The tactic worked in that neither Michael Portillo nor Norman Lamont put their names forward, but John Redwood, the candidate of the extra-terrestrial Right, still managed to inflict serious damage, denying Major the support of one third of Conservative MPs.
The threat of resigning to fight a leadership election seemed a powerful one, in that loyalty and name recognition would normally have been enough to see Kennedy through effortlessly. But he has left it so late, and in such unflattering circumstances, that it may not work now. All he has succeeded in doing is trap Mark Oaten, the party's home affairs spokesman, into saying that he would not challenge his leader for the top job.
The other factor that inhibited Liberal Democrat MPs from launching a full-blooded coup was the popularity with the members of the candidate who came second last time, Simon Hughes. The danger of forcing a leadership election in which Kennedy was not a candidate was even greater, in the eyes of many Liberal Democrat MPs, than the danger of an election in which he was a candidate. It must be suspected that the fear that Hughes would become leader was what stayed the hand of Sir Menzies Campbell, the party's deputy leader. He was elected unopposed to that post and must know that the membership tend to regard him as "too Tory" for the top job.
Now, however, the calculations have changed. The Kennedy who intends to fight a leadership election lasting several weeks is not the Chatshow Charlie of fond memory, but a recovering alcoholic who admits that he should have been willing to be open about his problem before. It may be that a nonconformist party will take a reformed character to its heart. It forgave Paddy Ashdown his sexual adventures. And many heavy drinkers and recovering alcoholics have made great contributions to British politics, Winston Churchill and Alastair Campbell to name but two.
But a leadership election is an unpredictable quantity. Ask David Davis. Oaten may have stood by his self-denying ordinance, but other MPs will put themselves forward. When Kennedy won the leadership six years ago, there were five candidates. It has been made more difficult to stand by the rule change passed - little noticed - at the party conference last year. That requires candidates to be nominated by 10 per cent of the party's MPs. That means seven, but there are enough varieties of unpredictable MP for that to be possible for three or four contenders. Even Simon Hughes - against whom the rule change was widely suspected as being aimed - is said to be confident that he can round up the necessary signatures.
If there are candidates, then their qualities are tested against Kennedy's. Kennedy has led the party in two election campaigns in which it increased its number of seats, but he has no exceptional qualities that justify any belief that he could do it again. Against a stunning display of creative and unexpected politics from David Cameron - whatever one thinks of the depth of Cameron's thinking - Kennedy offers only more of the same. More of the same, with added personal problems.
The nuclear option may turn out to be a mirage. It was always part of a pact of mutually assured destruction. He had the threat of a leadership election. His MPs had the threat of a vote of no confidence. Now it is clear that they have no confidence in him - yesterday's statement may be enough to persuade party members, for the time being, that Kennedy deserves their support. But he is not prepared to put that to the test with his own MPs. He does not trust his appeal to convince the people with whom he has to work politically.
That changes the chemistry of a leadership election too. Not even Liberal Democrats, nice people that they are, can easily re-elect a leader who does not command the confidence of his parliamentary colleagues.
The writer is chief political commentator for The Independent on SundayReuse content