"Just because you're paranoid doesn't mean that they they're not out to get you," so the old joke goes. The normally well-adjusted, thoroughly sensible Charles Kennedy has never shown much sign of paranoia, but his parliamentary colleagues are certainly out to get him.
They tell him to "raise his game" in the full knowledge that he can't. They're spooked by the appearance of new kid David Cameron on the block, even younger than Charles Kennedy, who may, in time, come to use the line that he is a "fully-paid up member of the human race", which used to be Mr Kennedy's monopoly. Colleagues aren't happy about the impact Mr Kennedy's isn't making. They're briefing the press, big-time.
Well, Kennedy's critics are right. The last election was an opportunity that comes only once in a generation. It's often the case that the Liberal Democrats and their predecessors have prospered when the Tories have collapsed, as in the 1970s and 1990s. Sometimes, though less often, they've done well when Labour was weak, as in 1983, say.
What was very special about 2005 was that both of the main parties were out of favour with the electors, if for radically different reasons. Tony Blair's record had turned to resentment and disappointment, especially on the war, but also on public services. The Tories were still divided and headed by a competent but unlovely leader.
There were, in other words, two loads of protest votes going begging, in Lotto terms a sort of political rollover, and the Lib Dems didn't capitalise on that nearly as successfully as they might have done. Mr Kennedy did not do badly - more seats, more votes, doing better than Paddy Ashdown. However there is a nagging sense that maybe, just maybe, 2005 could have been more of a Lib Dem breakthrough than just another step forward. Kennedy missed the open goal, and the votes went begging, heading off to the fringe parties, and the rest staying home.
Since the election, things have got worse. David Cameron is still a novelty, and the Tories are resting such extravagant hopes in him that one wonders how they might cope if he, too, turns out to be a dud. But for now he seems vigorous and assured, with a better sense of strategy than Charlie, and a party behind him that is desperate for success. The Tories know they need to win back not just seats lost to New Labour, but all those constituencies in the West Country and the home counties where the Lib Dems are now established.
The plausible Mr Cameron may well be able to win back moderate Tories who defected to the Lib Dems in the chaos and extremism of the post-Thatcher Tory party. Mr Cameron has even started talking about the environment, something Liberal Democrats may mock, but ought to take seriously. If I were a Lib Dem MP, I too would be getting worried about this Cameron guy.
So the Liberal Democrats need a new leader - but, true to form, they are going about it in completely the wrong way. This semi-public campaign being waged by some of Mr Kennedy's senior colleagues will leave the party with the worst of all worlds. They have certainly destabilised his leadership - witness Cameron's cruel jibe at Mr Kennedy at Prime Minister's Questions yesterday about the Lib Dem's new "decapitation strategy".
Yet the Lib Dem plotters have very little chance of actually unseating him. Constitutionally he cannot be easily challenged, but in any case who gets to lead the Liberal Democrats is not up to the Liberal Democrat shadow cabinet, the parliamentary party, activists or indeed we scribblers in the press. It is up to the ordinary party membership and they, I am fairly sure, want nothing more than for Mr Kennedy to be left alone to get on with the job and nothing less than Menzies Campbell running the shop.
I am in the happy position of not having voted for Mr Kennedy in the leadership election he won in 1999. In the preferential voting system predictably favoured by the Lib Dems, I placed him sixth out of the six candidates available. I'd do the same again. Were there an election to replace Mr Kennedy now, I hope there'd be fewer candidates and more choice. The party needs to decide what it wants to be before it decides who leads it.
Mr Kennedy's "chairman" style facilitates a useful ambiguity, but long-term it isn't a tenable approach. A leadership election could set the party on a clear course. So let's hear what kind of vision David Laws, or Nick Clegg or Ed Davey or any of the other young talents would like to offer. But getting rid of Kennedy would be very messy. I fear we won't be reading their leadership manifestos anytime soon.
The writer was press secretary to Paddy Ashdown