I've been so disappointed with the Lib Dems over the last few years. I'm not just going on about their useless 'leader' either.
Their biggest mistake has been in tactics and ideology. They really did have a massive chance to become the second party in 2001 and 2005. The Tories were extreme and right wing and had unpopular right-wing leaders like Duncan Smith, Hague and Howard.
The sensible thing would have been to target the vast number of winnable Tory seats where they were in second place rather than the handful of winnable seats in Labour areas. But instead they positioned themselves to the left of Labour on some issues. Their proposal to raise taxes for the rich was hardly going to win them many Tory voting converts in wealthy Tory areas.
In the short term the 'progressive consensus' helped Labour because both us and the Lib Dems talked of the need to spend more on public services and this only highlighted how out of touch the Tories were in talking incessently about tax cuts.
But in the long term by positioning their image to the left (sometimes even left of Labour), the Lib Dems missed an historic opportunity to win dozens of winnable seats off the Tories and as a side effect also allowed the Tories to hold on in seats that Labour would have won, by splitting the progressive vote.
Instead of winning a few seats off Labour and moving slowly up to 62 seats, they could have decimated a weak Tory party and be sitting on 80 or maybe even a 100 seats. The Tories would have lost even more to us. With the Lib Dems and Tories both on around a 100 seats, it would have been clear the Tories were finished for ever and a lot of Tories (and maybe even a few national newspapers would have jumped ship). By their ineptitude, the Lib Dems have saved the Tory party.
Having the Lib Dems as the real opposition to Labour, would have been good for the country and good for both parties and maybe even electoral reform might have got onto the agenda and we could have got rid of this unfair system that prevents any real choice for the electorate.