After their disastrous performance at the 2015 general election, the Liberal Democrats had to confront a fundamental question: what are they for?

To many their slogan – “a stronger economy and a fairer society” – was indicative of a failure to come up with a positive definition of what liberalism meant, instead offering simply to mediate the two main parties.

Post-Brexit, of course, they have found a definite revival in their fortunes as a haven for continuity Remain voters. But the party still needs to decide whether to try to stick to the more realistic, party-of-government attitude adopted by Nick Clegg or revert to being an opportunistic party of protest.

Recent events over Syria suggest it is leaning towards the former, although old habits die hard.

Tim Farron has written in the Guardian that he supports President Trump’s missile strike on a Syrian Government airbase, launched in response to the Assad regime’s use of chemical weapons. Unlike Clegg, the current Lib Dem leader didn’t vote for action against Assad in 2013.

Moving from being anti-intervention to pro-intervention, after leaving office, shows how far some in the party have come from the days of Charles Kennedy’s leadership.

The late MP for Ross, Skye, and Lochaber, who passed away shortly after losing his seat to the SNP at the last election, look the Lib Dems to their best-ever seat total at the 2005 general election on the back of trenchant opposition to the Iraq War. So closely did the party become associated with this cause that it was hard to remember its earlier support under Paddy Ashdown, a former Royal Marine, for intervention in Bosnia.

Still, Farron clearly hasn’t been able to leave his opportunist instincts entirely behind him. He’s joined in the chorus calling Boris Johnson a “poodle of Washington” after the Foreign Secretary pulled out of a planned trip to Russia. Such criticism isn’t particularly consistent: Johnson withdrew in order to allow Rex Tillerson, the US Secretary of State, to deliver a coordinated position after a meeting of G7 foreign ministers in Italy.

But if that’s as far as Farron allows the urge to play to the gallery to take him, he’ll emerge from his dealings on Syria with more honour than Ed Miliband. The question must be whether or not he can bring his party, many of whom look back fondly on their halcyon days under Kennedy, with him.