Celebrations at a return to power are being tempered by deep anxiety as the Liberal Democrats' autumn conference in Liverpool gathers steam.
With the party in power for the first time in many decades this should be an opportunity for triumphalism. That seemed unlikely after the party's number of MPs dipped below 60 at the general election. Yet Nick Clegg's much-vaunted 'kingmaker' status gave the party the opportunity to return to government. Liberal Democrat policies are now being implemented as part of a coalition with the Conservatives. "The party will want to celebrate that," Clegg's parliamentary aide Norman Lamb predicts.
Lamb claims "overwhelming support" for the decision to enter into a formal deal with the Tories endures. This was first established at the specially convened post-election conference earlier this summer, when - behind closed doors - party delegates backed Clegg's decision. That consensus always seemed artificial. The next few days in Liverpool are expected to demonstrate a very different reality.
"I think the mood will be a bit jittery," Julian Astle, the director of liberal thinktank Centre Forum, predicts. Not many Lib Dems went into politics to slash the size of the state, yet that's exactly what the coalition government will do on October 20th when it unleashes details of a comprehensive spending review set to cut most government departments' budgets by at least 25%. This is "unfamiliar and uncomfortable territory" for your average Lib Dem.
The 'average' Lib Dem sums up the problem, for he or she is farther to the left than the party's leadership. "These parties are a little bit like two towers that lean towards each other at the top," Astle explains. The leaderships of the coalition parties are much closer than those who turn up to the conferences, which is why the enduring differences between their members will be highlighted in the next few weeks. These are "two different types of beasts".
It's OK to be confused about what happens next. In single-party government the policy-making process is straightforward. But with two parties in power the junior party must be careful that its temperamental conference does not deviate from the party line. Somehow, this has been institutionalised; one agenda point on free schools and academies sees the "concerned" Lib Dem conference proposing to disagree with the coalition government. As Lamb acknowledges, Britain's third party insists its conference is "sovereign" in making party policy - raising the prospect of Nick Clegg defending a policy in his role as deputy prime minister but condemning it as the leader of his party. Can this really be made to work?
A "lively debate" should be facilitated, Lamb says, displaying typical Lib Dem enthusiasm for hanging out dirty washing in public. "You've got a vibrant party that has a soul and is determined to debate key issues - and sometimes challenging the government." The party has only signed up to the coalition agreement, after all. Beyond that there is all to play for. The leadership wants a self-confidence about Lib Dems' philosophy, as the party's ministers go up against the might of the Tory party in negotiating stances on future issues. "The conference is the opportunity to influence that debate."
This is a defensive interpretation of what Liberal Democrat conference should be for. It's one based on the party's membership being outside the government, not a part of it.
The prospect triggers instant concerns for Centre Forum's Astle. "I think one of the tasks Nick Clegg and his colleagues have got at this conference is to give the party a sense of ownership of the whole agenda," he argues. "They need to make them feel comfortable with, even proud of, what the coalition is doing across a wider range of policy areas than just the civil liberties and the political reform agenda." Failure to do so reinforces the impression that the party is barely in power at all, trying to influence decisions being taken by a small circle at the heart of government.
The mismatch this creates would be easier to bear without the relative vulnerability of the Liberal Democrats. Public sector cuts will prove especially unpopular in the least resilient areas - the northern urban heartlands where the main struggle is typically a battle between Labour and the Lib Dems. Liverpool, where local councillors are on the verge of a mass mental breakdown at the prospect of having to defend the cuts, is a painful case in point.
Nervous Lib Dems will need persuading that the situation is not quite as bad as they fear. So a decent bet for Lib Dem ministers keen to keep their jobs will be to point to the longer-term pluses of being in government.
Attention will inevitably focus on electoral reform, but success in the 'yes' campaign launched by Clegg as the conference began is far from guaranteed. Fixing the credibility gap looks like a surer proposition. Convincing voters that the party is capable of taking difficult decisions and governing in the national interest will be a major accomplishment. But it requires a big change of mental attitude, Astle warns.
"For a long time now Lib Dem MPs have become very used to being able to tell every passing lobby group what it is they want to hear. What they are unused to doing is take decisions which inevitably are going to upset interest groups, and take responsibility for those decisions. But these things take time and there is a cultural shift that is required as they go about that. This conference represents the first step on that journey."
The bittersweet taste of this celebration remains difficult to get away from. "They're probably cursing fate that after eight decades of opposition the moment they come into government is precisely the moment this most difficult of fiscal challenges has to be faced up to," Astle muses. "But there's a certain amount of determination within the party to see it through." We'll find out exactly how much resolve this week.