Vince Cable said he thought tribalism in British politics had reached a new pitch, and suggested this would suit the Conservatives most.
We have reverted to an extraordinarily tribal way of looking at politics. We all paid lip service to the local contests. Good councillors and bad councillors were treated the same way. This was a referendum on national government. That risks there being no respect for local government - both libraries, which are a local issue, and the NHS, which isn't.
Cable suggested that the Conservatives would be the main beneficiaries of a tribal and polarised politics.
Trbalism has always been part of politics, but it is now at a different pitch. Some in all parties like Tony Blair, Cameron, many Liberal Democrats have tried to have a more open, less tribal politics, but we now have a very rancourous return of political tribalism.
The question is where does it lead?
We have a lot of people in this country who will be disenfranchised in a much more tribal political culture.
In the short-term, it is very bad news for my party. We get very badly hammered if politics retreats into its core votes, though we did discover we had a core vote of our own of around 15%. If you had asked me what our core vote was a year ago, I would have said it was a lot lower than that.
My question to the Labour party would be this. Do you really believe, in that return to a more strongly tribal politics, which party is best placed to mobilise 40% of the vote - with the ground machine and the funding base to do that. If you think its the Labour Party, then I would say you are going in the right direction.
Cable was warmly received by the Fabian audience when he made his surprise appearance during the event. He spoke of how he had always been committed to engaging with Fabians and debates across the Labour and LibDem party boundaries. His call for a less polarised and caricatured debate about the causes of the economic crisis implied a distancing from the Liberal Democrats leading partisan attacks on Labour's record, though Cable defended his own track record on arguing against a 'back to business as usual' approach to the crisis.
But Cable was criticised and challenged from the Fabian members when he described the differences between the major parties over spending cuts as "an extraordinary ideological war around microscopic differences over spending cuts", and was challenged over why he had changed his mind about the need for early spending cuts in particular.
Andy Burnham, Labour's election coordinator, won applause for questioning whether anger at the Liberal Democrats from their own voters could fairly be described as tribalism.
It might be too convenient to label the anger that many of those who voted Liberal Democrat feel as tribalism. There are a lot of people felt that their votes had been stolen. They were centre-left people, voting for a centre-left party. They were not tribal people. Many of them had voted Labour in 2001 and then LibDem in 2005. It was the people who were not tribal who were most angry with the Liberal Democrats.
Cable acknowledged this point, noting that Liberal Democrats, included himself, had won a fair number of votes from those who were Labour people, voting LibDem to keep the Conservatives out, while other LibDems won anti-Labour votes from Conservatives: "we are having to operate in a different world; our base is going to change", he said.
Burnham had told the Fabian progressive fightback conference in London this morning that Labour needed to focus its fire on "the real enemy": the Conservatives. But he couldn't resist one observation on the political troubles of Nick Clegg, arguing that the LibDem leader had Stockholm Syndrome, but that Labour's advances against the Liberal Democrats had now changed the Coalition.
"Our progress has brought a significant political consequence. It has changed the Coalition. David Cameron's cover has been blown. He cannot hide behind the Liberal Democrats any longer.
We have released the human shield from the hands of his captors - but it's clear that he's beyond saving. The more I hear Nick Clegg talking about life in the Coalition, the clearer it is that he has a classic case of Stockholm syndrome. He could go free, but he is drawn back to his captors, pathetically grateful.
Now, 'muscular liberalism'. That could be the theme for a Fabian pamphlet.
It sounds a bit dodgy to me. If all of us were to sit down with a blank sheet of paper and write down one hundred objectives about the Liberal Democrats, does anyone think that the word 'muscular' would appear on them.
I could go on but I will stop myself. The electorate have made up their mind about the Liberal Democrats. Labour must now get down to the real business and focus all of our efforts on the real enemy", said Burnham.
Earlier, Burnham had told the Fabian conference that the trauma of Labour's 2010 defeat was easily underestimated:
"We may not have been sparked out on the canvas, as the Tories were in 1997, but we were stopped in the tenth round, looking pretty bloody and beaten up". The result had been a "low point in Labour's history", only just exceeding the party's share of the vote in 1983.
Labour should not have a rose-tinted view of its local elections results but had made progress, particularly recovering centre-left support from the Liberal Democrats.
Burnham argued that it was important that Labour had recovered as a campaigning force - with 50,000 new members joining in the last year, helping the Labour party to make more contacts in the first four months of 2011 than in the same period of the General Elecion year, speaking ahead of a session with Peter Hain on the 'refounding Labour' process this afternoon.