On his own account, Cory Bernardi has had a good week. Having assembled a coalition of rightwing Liberals, even more rightwing crossbenchers, and Derryn Hinch to try to force changes to the Racial Discrimination Act, he feels that his crusade is poised for victory.

He told the Australian this week that before the election, watering down Section 18C of the act was supported by “only a few of the crazy rightwingers like myself”. Now he has 20 senators on side.

A lot of post-election commentary on the Senate has focused on the danger posed by Pauline Hanson and her possibly-sovereign-citizen colleague Malcolm Roberts. (He denies being a sovereign citizen.)

Progressives do need to be concerned about the re-entry of Hansonist politics to the parliament. But Bernardi’s comments, and his career, show us how the ideas of the far right become embedded at the heart of the political system.

The 18C fight is just the latest in a string of often-successful attempts by Bernardi to use his position and the parliament to pursue obsessions which overlap with those of the far right.

For example, Bernardi was instrumental in bringing about a Senate inquiry into “third party certification food”, which included halal food. The Sydney Morning Herald described submissions by members of the public to that inquiry as a “torrent of hate” – the Senate committee running it noted that much of what it received was “inflammatory, derogatory, and, in some cases, even obscene”.

During the hearings, Bernardi engaged in a line of questioning which may have implied that the NGOs involved in halal certification might be funding terrorism, saying that they were “involved in the establishment of mosques, schools, da’whas, bookshops – the whole thing. They receive halal certification funds which then flow through the system, and where they end up no one really knows. But we do know that extremist organisations in Australia are funded by someone and they are linked, in many cases, back to those not-for-profit bodies”.

Angela Jamieson from Austrac, which monitors terrorism funding, answered that there was no evidence of halal certification funding terrorism. But Bernardi’s question echoed one of the favourite conspiracy theories of the Islamophobic far right – from Reclaim Australia to One Nation – that a halal “tax” on basic foodstuffs may be funding Islamic terrorism.

In turn, this conspiracy theory echoes the antisemitic myth of the “kosher tax”, pushed by an earlier generation of far-right groups.

Bernardi’s appetite for conspiracy theories does not end with Islamic food practices. In his 2013 book, The Conservative Revolution, Bernardi wrote that religion has been “attacked and derided by cultural Marxists”, and that “cultural Marxism has been one of the most corrosive influences on society over the last century”.

Last year, criticising the Safe Schools program which aimed to address the bullying of LGBTQI children, Bernardi claimed that it indoctrinated children with “Marxist cultural relativism”.

In those instances Bernardi explicitly echoes the conspiracy theory of “cultural Marxism”, which holds that the (mostly Jewish) Marxist intellectuals of the Frankfurt school worked to subvert western values by preaching cultural relativism.

The story was cooked up by a rightwing thinktank in the early 1990s as a means of touching off a culture war. Now it is frequently retold in some alarming places – like neo-Nazi site Stormfront, by Professor Kevin MacDonald, who claims that Judaism is a “group evolutionary strategy” aimed at securing civilisational dominance, and by former KKK member and far-right politician David Duke.

The antisemitic overtones of a theory that references subversive Jews seem not to have occurred to the Australian right, where the “cultural Marxism” theory is increasingly mainstream.

Dominic Kelly, whose PhD research at La Trobe University focuses on political advocacy groups and thinktanks of the right says, “It doesn’t surprise me at all that people like Bernardi would pick up on that language, but neither would it surprise me if they weren’t aware of the antisemitic undertones.”

Now, in attempting to repeal section 18C of the Racial Discrimination Act, Bernardi is no longer just referencing far-right political concepts, but actively cooperating with far-right political actors like the One Nation party.

Though he says he is not engaged in an attempt to undermine Malcolm Turnbull, Kelly says Bernardi is a leader in an increasingly intransigent group on the hard right of the Liberal party.

This hardcore who backed Abbott, and who still back Abbott, have become a win-at-all-costs grouping. In a sense the Coalition has become unmanageable. I don’t see a simple, peaceful way out of this. Unless the right get what they want every time, they will not stop the fight.

That pattern of behaviour has been defined by issues where Bernardi uses far-right concepts, gives far-right voices a platform, or actively collaborates with far-right parliamentarians.

And overwhelmingly, they are issues where marginalised and scapegoated groups – like Muslims, queers and racial minorities – either come under more scrutiny and surveillance or have some of their few protections removed.

The Hansonist resurrection is alarming, but any power they may come to wield will be completely contingent on their ability to cooperate and make common cause with larger blocs in the Senate.

Cory Bernardi, meanwhile, sits in the party room of the governing party, and in the first sitting week of the new Senate, he’s shown his willingness to build bridges between that party and One Nation.

That would be less concerning if a strong, popular and powerful prime minister was able to hold the demands of people like Bernardi at bay. But Malcolm Turnbull’s majority is precarious, and the demands of rightwing Liberals like Bernardi and his lower house colleague George Christensen are insatiable.

As Kelly points out, the more likely future is that the Liberal party moves even further right.

“[Turnbull] has already compromised so much for them. They will accept nothing but total victory, like Tea Party Republicans.”

The problem going forward may not be so much One Nation or other far-right groupings as such, but the extent to which which they can collaborate with or influence segments of the Liberal party, and through them, the government.

In their study of rightwing populism, Chip Berlet and Matthew Lyons caution that an exclusive focus on extremists risks us failing to “recognise the frequent direct linkages – ideological, organisational and economic – between rightwing and mainstream political forces”.

The real damage done by extremism is in the influence it exercises on the mainstream right:

The danger associated with rightwing populism comes not from its real or potential bids for power, or even from its day-to-day violence and bigotry, but from its interactions with other political forces and the government.

The person and career of Cory Bernardi is a good way to begin understanding those linkages, and dangers in Australia, now and into the future.