There is a new political force in South Australia: the Marty Party. Ostensibly Liberal conservative, this one-member organisation’s real purpose is power; not the trappings of office, but the office itself.

Martin Hamilton-Smith, the headstrong but accident-prone former Liberal leader whose Dodgy Documents own goal prompted an extraordinary campaign of destabilization against him by his own offsiders, has been described by some in his party (most of whom have orchestrated a leadership coup at some time or other) as a serial challenger and a destructive influence.

That’s fair; he challenged Kerin, Evans and Redmond, and has now walked out on Steven Marshall. If he ever relinquished his membership of the Marty Party and officially signed on with the ALP, he’d probably fancy his chances against Jay Weatherill at some stage too.

But right now, the Premier is unassailable. He has a workable majority, which quickly becomes unworkable if he is displaced. It’s been a masterstroke of simultaneously hobbling both the Liberal Opposition and his factional opponents within. But despite all that, this isn’t really about Weatherill or Labor.

It’s about Martin Hamilton-Smith’s will to power, and the state Liberals’ almost pathological aversion to it.

If it’s true that MH-S was the fourth Liberal MP approached to join the Government, and the Opposition was aware of this fact, why wasn’t the leadership both in parliament and the party administration canvassing to ensure one of the many discontents wasn’t about to be wooed? Why; because the party thrives on discontent.

If some poor soul were ever to write a book documenting the SA Liberal Party’s lost generation, it would be a cautionary tale of self-imposed failure.

Internecine warfare derailed its prospects through the 1980s, personal ambition continued to undermine what should have been a long stint in Government through the ‘90s that ultimately fizzled out after only two terms.

Children born into factional fire continued to wage the battles of the Bannon era through Rann’s two and a half terms. And while, theoretically, these factional warriors have now slowly, painfully learned their harsh lessons, the psychology of the party is so fixated on internal influence that the destructive impulse remains hard to shake.

The Evans camp, despite determination to be a part of a Marshall administration, still felt the need to pour resources into pointlessly trying to unseat Bob Such in Fisher, a folly that probably cost the party Government. And both factions have made it practically a sport to marginalise and besmirch the reputation of Hamilton-Smith, the only Liberal leader in a decade to articulate and attempt to sell a vision for Government. This Marty-bashing seemed to be of little consequence; he had, after all, played his final hand with his challenge to Isobel Redmond, and fallen one vote short. He was destined to see out his days as a mid-level shadow minister.

So while this week’s amazing defection is very much Weatherill’s coup, it is Marty’s masterstroke too; with one decisive blow he accomplishes his two burning ambitions: to govern, and to wreak revenge.

I wrote the following words in March 2010, just after Isobel Redmond had demanded a second ballot to oust MH-S as her democratically-elected deputy: “The Liberal Party owes MH-S a lot more than MH-S owes the Liberal Party. There are few people who have given so much to their cause only to be treated so shabbily in return.”

It’s true that Labor picked its successful target wisely; the soldier turned businessman turned politician likes to be the centre of attention; his conceit is to forever see himself charging in to save the day.

While afflicted by that common political ailment – an over-inflated sense of ego and entitlement – he has always been something of an outsider in the Liberal party-room, a fact that was once his major selling point; “I’m not part of a feudal dynasty,” he would say, outlining his credentials.

But he has become increasingly isolated; despite running with Marshall against Redmond and describing the young Pyne acolyte as his “political soulmate”, he found himself ostracized both in middlebrow portfolios and in his lack of influence over his one-time offsider.

Sure, it is a major moral leap to go from being ostracized to completely gutting your party’s electoral prospects. Nonetheless it’s time for some of the third-party hysteria of the past week to subside. True enough, in politics jettisoning the party that got you elected for its rival is seen as the ultimate betrayal, and that’s valid; it’s a burden that Hamilton-Smith must now bear till the end of his days.

But with even the Tiser’s usually diffident front-page headline screaming ‘Treason’, there appears a concerted effort to demonise the Member for Waite.

We certainly didn’t see much of this outrage when Kris Hanna jumped ship to the Greens, nor when Rob Brokenshire re-entered parliament under the Family First banner.

True enough, the affront seems more significant coming from someone who once led his party, and still apparently harboured aspirations to do so. But let us dispel this notion propagated on talkback and social media, and even among some political commentary, that he is doing it to line his pockets or to chase the perks of office, such as chauffer-driven travel. Seriously? In 2012 his Mitcham home was on the market for $4 million; the dude’s loaded. He likes to tinker with vintage sports cars in his spare time; I’d suggest he’d consider the ministerial Holden something of a demotion.

The Liberal party-room, with a few notable exceptions, can’t complain about loyalty. It never had any. In some ways, the surprise was not so much that Hamilton-Smith jumped ship, but that three fellow MPs before him chose not to.

No, at its heart it is the fact that his defection leaves the Liberals so badly wounded that rankles. He was one of the few pushing the case for a big-picture policy manifesto; while his hubris can lead him into folly, he remained one of the Libs’ stronger parliamentary performers.

Moreover, he appears to have taken his devoted office staff over with him, all of them to date loyal Liberals. What does this tell us? And the fact that his policy confidant, Ben Page, seems to have joined him in his defection is perhaps a greater injury to the Liberal cause long-term than Hamilton-Smith himself; he is one of the sharpest policy brains on either side of politics.

This week’s bombshell came as a shock to almost everyone, but on reflection it shouldn’t perhaps have been so surprising. After the election, Hamilton-Smith was incandescent that the Liberals had persisted with a small target strategy, with everyone from Evans to Rob Lucas to Jeff Kennett getting in Marshall’s ear to promote the policy-lite approach. He firmly believed that the economy would come good eventually, and that the Liberals’ only trump card, Labor’s fiscal mismanagement, would be forfeited.

Like so many in the Opposition ranks, he was starting to recognise his political mortality, and to realise that his entire parliamentary career – the best years of his professional life – might well be wasted in fruitless, carping Opposition. Now 60, he realised he would only ever serve one term as a minister – if he was lucky.

If the Libs won in 2018, he would be 64 and just setting off on his ministerial career. If they didn’t, he’d have to content himself with the memories of his three months as Tourism Minister in the dying days of the last Liberal Government. So all this talk of him losing his seat in a bitter backlash in 2018 is immaterial.

Either way, he was only going to get four years as a Government frontbencher. He just chose to have it now, and to make it certain.

It’s funny that those complaining the loudest are the same who insisted Weatherill would be unable to maintain stable Government, and those who lamented Labor had lost touch with the business community.

Weatherill is now assured stability, and has anointed a minister heretofore considered a champion of business, but all anyone evidently cares about is the poor, wronged SA Libs.

The Liberal party-room, with a few notable exceptions, can’t complain about loyalty. It never had any. In some ways, the surprise was not so much that Hamilton-Smith jumped ship, but that three fellow MPs before him chose not to.

Betrayal and disloyalty are part of the culture in the SA Liberal Party and MH-S has borne the brunt of it more than most.

If there is one person who should feel genuinely aggrieved it is Steven Marshall, an energetic and fresh-faced (though decreasingly so) young leader only just beginning to truly comprehend the baggage that continues to drag down the office he has inherited. He has been, it seems, poorly advised and poorly served by those in whom he placed his trust, and now he has been knifed by the man who inadvertently propelled him into the leadership.

He is not a career politician, and he must now realise the pipe dream of seizing Government before the end of the fixed four-year term has evaporated. Having started 2014 confident of becoming Premier, he must now contemplate the prospect that he will never even see the inside of a cabinet room. And the party he leads, that only three months ago believed it was on the cusp of a golden new era, is fast writing off 2014 as an annus horribilis, among many anni horribiles.

When Hamilton-Smith’s most bitter rival, Iain Evans, outlined the Liberals’ costings in the final days of the March campaign, he was asked whether he continued to harbour leadership aspirations, given the conservative faction’s sideshow campaign in Fisher. His response was impassioned: he had spent some of his best years trawling through the muck of factional spats and misguided ambition; now, he just wanted the opportunity to be a senior minister in Government.

Martin Hamilton-Smith seized that opportunity this week; for his former colleagues, though, it seems further away than ever before.

Tom Richardson is InDaily’s political commentator and Channel Nine’s state political reporter.