Multi-party electoral systems like those in the UK and Germany leave room for parties that are (relative to the altnernatives, at least) socially liberal and fiscally conservative. And what ends up happening is exactly what Brink Lindsey describes in his excellent book The Age of Abundance: libertarians (or liberals, as they’re known in Europe) occupy a kind of “centrist” position, acting as junior coalition partners and moderating the big-government tendencies of both the left and the right. At a minimum, the Britian and German experiences show that there’s nothing inherently contradictory about a left-libertarian movement.Sound familiar? Alex Massie argues similarly, here.
The British and German experiences also provide support for the Boaz/Kirby argument about the libertarian vote in the US. The FDP and Lib Dems have historically gotten around 10 percent of the vote, on par with Boaz and Kirby’s estimates of the size of the libertarian vote in the United States. Boaz and Kirby also argued that the political effectiveness of libertarians is maximized when libertarians aren’t too closely tied to either end of the political spectrum. A credible threat to walk away from the Republican Party and support Democrats will give both major parties an incentive to take libertarian voters. That certainly seems to be confirmed by recent developments in the UK, where the Liberal Democrats were able to push their coalition government in a direction more friendly to civil liberties.[emphasis added]
In New Zealand, the intersection of the top quartile of economic liberals and the top quartile of social liberals has roughly 6.2% of voters. But there's no reason to expect that a liberal party couldn't draw support from economic liberals who were social moderates and from social liberals who were economic moderates as well, so long as they cared more about the dimension on which they were liberal. That would push support up into line with what's found internationally.
Shame that what would have been our liberal party instead seems intent on being a right-wing rump to National.