I bumped into former Lib Dem leader Paddy Ashdown at Heathrow yesterday, and found myself on the same flight. We were able later to swap stories about random encounters with passers-by. In his case, someone saying to him ‘didn’t you used to be Paddy Ashdown?’, in mine someone asking me if I was Alastair Campbell and, when I confirmed I was, telling me his name was Alastair Campbell too, adding ‘have you any idea what my life has been like these past few years?’

I always had a lot of time for Paddy, even if I was never exactly persuaded of TB’s strategy for dealing with his party. He was a good third party leader and has since gone on to do important and valuable work, particularly in Bosnia. The skills he deployed there would not have gone amiss in Afghanistan.

But he got me thinking about the role of the Lib Dems today. I cannot claim to be an expert on Lib Dem internal politics. Nor can I claim to have detected a political or electoral strategy of any great clarity. That may be deliberate on the part of Nick Clegg, who will be hoping to garner support of people tired of Labour but not remotely convinced of the Tories under David Cameron.

But as two powerful political impulses collide – namely ‘time for a change’ and ‘are the other lot really up to it?’ the buzz around the prospect of a hung Parliament will grow, and Clegg’s positioning within the bigger political picture will have to become clearer.

The Lib Dems have a reputation as good local campaigners, able to tailor their messages to suit local audiences. But when it comes to a general election, people know they are electing not just their own MP, but the government and the Prime Minister. And they know that the Prime Minister will be either Gordon Brown or David Cameron.

As to where Clegg stands on the possible ramifications of a hung Parliament, he will not be able to get through an entire campaign without having the outline answers ready. Would he be willing to work in alliance with Labour? Would he be able to do the same with the Tories?

I suspect, whatever his personal preferences, that he will not be allowed to do either. There are fiercely anti-Labour forces in his party, and fiercely anti-Tory forces as well. I’m not convinced they can be reconciled.

All of which makes the prospect of a hung Parliament not terribly attractive in a country not used to its politics of compromise. Which means the country may prefer to give a clearer verdict one way or the other. Labour or Tory. No messing around in the middle. So the Lib Dems get squeezed. Or am I missing something?