Some on the left make the mistake of thinking Cory Bernardi's danger to our polity lies in promoting unfashionable or nonsensical views. But the real danger is that Bernardi shifts the goalposts on what we consider outrageous, writes Andrew Porter.

In September, Prime Minister Tony Abbott famously quipped, "Happy is the country which is more interested in sport than in politics because it shows that there is a fundamental unity." A noble sentiment, well expressed.

And so it went that as the hopes of cricket fans across the country for a real Ashes contest - instead of the so-called “Pomnishambles” - were dashed, so too were Abbott's calls for fundamental unity cruelled by the most predictable of interlocutors: his one-time far right-hand man, Cory Bernardi.

Politics is hardly at the forefront of most people's minds at the best of times. It's even less so in January. And the media cycle isn't exactly running at full bore as we all enjoy our holidays, or try to spend as much time with family and loved ones as we can over the summer.

Latika Bourke's report yesterday on Cory Bernardi's most recent adornment to the literary firmament crashed through that relaxed, apolitical summer.

The latest addition to the many wisdoms of Cory included the Senator decrying a link between "non-traditional" families and higher levels of "criminality among boys and promiscuity among girls" - quite the logical progression. He argues that the secular nature of our polity, which underpins our plural, multicultural society, is key to our country having lost its way, and that Christianity is under siege from both the Greens and Islam. He maintains that there is a rampant "death industry" pushing abortion as a form of birth control.

These are worthy entries to the canon of headline-grabbing Bernardi-isms. The best example of Bernardi's approach was his extraordinary claim that the path to bigamy and bestiality is paved with same sex marriage. It was undoubtedly one of the most profoundly offensive contributions we've heard from a politician in living memory.

This was a bridge too far for some of his usual fellow-travellers, who range from the IPA to the always entertaining Australian Liberal Students Federation (who revel in being more idelogically "pure" than their Young Liberal friends) among whom Bernardi's views on throwing off the yoke of the state earn him that most hallowed of Tory sobriquets, "sound".

They like that he talks a big game on the ABC - recently complaining that it is crowding out commercial competitors (tell that to The Guardian and the Daily Mail) - the "warmist" conspiracy, unions, "excessive" wages, the "rights culture" and the "black armband" view of, well, everything. But when confronted with his more avant garde, if not radical, social conservatism, they give him little succour.

In response to his latest contribution, one wag countered yesterday that Bernardi is a soul whose intentions are good, yet misunderstood; that his unique way of saying "normal" families are to be preferred, that a laissez-faire approach to abortions isn't ideal, and that perhaps our industrial relations system isn't perfect, really isn't that controversial.

In isolation, maybe that's fair enough. But this is to strip back his mutterings to core or acceptable truths; it's the defence that says, "Well, what he really meant to say is..." Important debates sometimes require a gentle nudge here and there. Bernardi, though, starts national conversations by way of dynamite stick. He is far more interested in attracting headlines, appearing uncompromising and doctrinally vigilant (and attracting publicity for his latest tome) than he is driving or maintaining meaningful national debate. It's not a case of what he really meant to say. Clearly, he says what he means. And what he says is more often than not offensive.

Without a hint of sarcasm, Bernardi's website assures the reader that "common sense lives here". But he revels in controversy. His website extols a quote from a fellow South Australian, Fairfax scribe Mark Kenny, that he is "one of the most controversial figures on the national stage". To give the man oxygen is to feed the fire. But then, I'm just a child of a non-traditional family, sullied by step-parents and siblings, and other vestiges of immorality. I'm not to know any better!

Some on the left make the mistake of thinking Bernardi's danger to our polity lies in promoting unfashionable or nonsensical views. Nothing could be further from the truth. The more he speaks, the more he isolates himself from the mainstream that the leader of his party has relentlessly and effectively courted.

The real danger Bernardi and his ilk pose to our society is that he makes it harder for conservatives of goodwill to speak their minds, for fear of being cut down for not adhering to their all-or-nothing interpretation of what it means to be a conservative, increasingly a social measure as much as the historical economic divide of wet versus dry. Equally, he shifts the goalposts on what we consider outrageous, and by extension, what we consider acceptable or unacceptable; anything from a Latham-esque difference of opinion with a cabbie to Bill Heffernan's musings on childlessness seem tame when using Bernardi as a yardstick.

Every time the door shuts on Bernardi's hopes of promotion or advancement, you get the sense he's the victim; the little guy, the underdog arbiter of what's sensible in our crazily complicated workaday world, and what's not. But unlike most powerless outsiders, he is of course a Senator for South Australia, and a member of the government.

Not too long ago, our head of government, Prime Minister Abbott, said that he wants to appeal to, indeed champion, the "sensible centre".

The challenge for the PM is how to ensure that for every step he takes to the centre, those unencumbered by responsibility on the backbenches don't revel in taking two steps to the right.

The challenge for Bernardi is to articulate how his scribblings serve the interests of the people he's elected to represent.

While Bernardi was re-elected as a Liberal Senator in September, in keeping with his enthusiasm for individual performance-based contracts, perhaps he might consider hanging out his own shingle next time round.

Andrew Porter was press secretary to Minister for Defence Stephen Smith. He tweets at @andrew_porter. View his full profile here.