Parties make all sorts of promises to voters. Labour learned wherever possible to make promises based on inputs rather than outcomes - 'x' many more nurses and 'y' many more police officers rather than commitments to specific reductions in crime or health improvements.
There are the commitments you make to your core voters and those you make to the swing voters in order to improve your showing at an election. In traditional politics, Labour and the Conservatives have done more for the swing voters than for their core vote. Labour was often accused of chasing the 'Daily Mail voter' and the Conservatives' approach to civil liberties and criminal justice has been far to the left of Labour in government.
But we are not in traditional politics any more and there is a party in government that has an unclear view of its core and swing voters.
The Lib Dems do have a core vote of pro-Europeans, electoral reformers and civil liberties campaigners. But mostly, over the past 30 years, they have built up votes and seats by attracting disaffected Conservative and Labour voters: people turned off by the 'nastiness' of the Conservatives in the 1980s and 1990s, or by Labour's wars or Daily Mail agenda since then.
Clegg's hand-wringing betrayal over university top-up fees is not just a blow to student supporters; it will shake the confidence of all swing voters who thought they were backing a different kind of party.
Failure to deliver electoral reform in a referendum next May will be an earthquake that will subsequently hit the Liberal core vote. The perfect storm would be if the Government backed an American attack on Iranian nuclear facilities.
There is a saying that in politics, 'you can't please all of the people all of the time'. It looks as though Clegg is having a hard time pleasing any people at all.
- Alex Hilton is a political communications adviser and former Labour parliamentary candidate.