If Malcolm Turnbull eventually loses his leadership for a second time, his pathetic arse-over-tit performance on gun control this week will be remembered in his downfall.

Even the mere act of playing footsies with David Leyonhjelm over trading support for the Australian Building and Construction Commission restoration bill was stupid and morally questionable.  I don’t have a clue about the Adler lever shotgun, and whether five or seven shots makes it acceptable: to me, and I suspect most non-rural Australians, it looks a highly efficient semi-automatic killing machine in skilled hands.  But there’s awful symbolism in Turnbull’s even being seen as willing to trade away the one achievement above all others of John Howard’s government – sensible gun control that’s ensured there have been no mass shootings in Australia since Port Arthur in 1996 – to court the vote of an idiosyncratic libertarian senator who’s equally misread the Australian community’s will and picked the wrong symbol for his libertarian crusade.

Libertarianism and anarchism are closer to each other than first appears. Both are rooted in innate selfishness, and both give two fingers to the notion of the community reasonably ensuring its citizens are safe from harm, even if individual rights have to be infringed.  Arguably, keeping powerful guns out of the hands of those having no justifiable need for them is reasonable.

On the issue of gun control, however, purist libertarians unleash their inner anarchist to reject laws they don’t like. Governments should not pander to those instincts for political gain. Surely when it comes to guns, any guns, public safety trumps personal freedom: but in his zeal to get the ABCC bill through the Senate, Turnbull appeared to be willing to trade away such high principle to pass a double-dissolution trigger bill without resorting to a joint sitting.  Tony Abbott may have been unwise to intervene publicly and give Labor a political distraction it has exploited to the hilt for the last two days, but he was absolutely right: to backtrack on gun control, for the sake of a tawdry political deal, was utterly wrong.  He stated last night on the ABC’s 7.30 programme that he, as Prime Minister, didn’t sign off a guns-for-legislation deal with the ‘obsessed’ Leyonhjelm.

Any such deal now is a moral and political dud.  Leyonhjelm instead should take the ABCC bill on its merits and vote accordingly and not, literally, hold a shotgun to good policy.  As for Turnbull, he misjudged badly in indulging Leyonhjelm on guns.  He unwisely gave the impression that the government is driven by pragmatism without principle.

Whatever one says about Abbott and his romantic tendency to big government paternalism, at least he stands for something.  As with Howard, you know Abbott’s motivated by ideas, even if you passionately disagree with him, and them.  With Turnbull, however, it’s hard to say what bedrock core beliefs motivate his approach to both politics and policy.  Doing deals may be in his businessman DNA, but in politics there is a little matter of promoting the greater good and the common weal  in what you do.  After a year in the prime ministership, it’s still unclear whether Turnbull’s got that clear in his alpha mind.

At least by the end of Tuesday Turnbull accepted the danger he’d created for himself and affirmed the government’s firm commitment to holding the line on gun control, and started to regain the offensive from Labor. If Turnbull wants to stay leader, however, he needs to stop blowing in the wind and define what are his core and non-negotiable principles and beliefs, and at least try and reframe his leadership around them.  Otherwise, by this time next year he won’t be in the Lodge.  It may or may not be Abbott who replaces him, and last night Abbott again played down that possibility. But if it isn’t Abbott, there will be others.