The Australian version of the Conservative Political Action Conference (CPAC) kicks off on Friday, continuing the long tradition here of conservative groups importing ideas, rather than generating them.

This weekend’s event is a branch-office version of the reliably wacky, but troublingly influential annual US conference. Among other things, CPAC is generally credited with launching Donald Trump’s career as a Republican political contender, after he was invited to speak there in 2011.

In the US, the conference offers a forum for hardline rightwing Republicans. Trump headlined again this year, but he was joined by YouTubers Diamond and Silk; former VP candidate Sarah Palin; anti-immigration Fox News host Laura Ingraham; high-profile evangelist Franklin Graham; and Turning Point USA honcho, Charlie Kirk.

But CPAC has sometimes had trouble in deciding which speakers and which ideas cross the line, as conservatives become more open to radical right ideas on race, multiculturalism and immigration. In recent years it has invited, then disinvited, groups like the conspiracist John Birch Society, and individuals like Milo Yiannopoulos.

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The Australian version should make us wonder whether conservatives here, too, have trouble drawing a line around mainstream conservatism, and keeping more malevolent political currents at bay.

The problem is not that all of the speakers at CPAC are beyond the pale. Clearly, whatever leftwing people may think of him, former prime minister Tony Abbott could legitimately be expected to be on the platform at a conservative event. Same for former deputy prime minster, and current podcaster, John Anderson. Abbott’s closest adviser, Peta Credlin, now a conservative media star, is someone we would ordinarily expect also.

Rather, the problem is that these ostensibly mainstream figures are legitimising the far more radical figures farther down the bill at the conference.

Raheem Kassam, for example, is a former Breitbart London editor who, according to Labor senator Kristina Keneally, is a “career bigot”. Late last month, she asked that he be denied entry to the country.

Kassam has repeatedly made misogynistic remarks about UK politicians. He has spread false, antisemitic conspiracy theories about billionaire George Soros, who he claimed was “not Jewish and … a Nazi collaborator”.

His favourite target, however, is Islam. He has called the Muslim holy book, the Quran, “fundamentally evil”. He has called for a referendum on the wearing of the Niqab in public. In his time at Breitbart, he obsessively wrote about Islam in terms of terrorism and “jihad”, and alleged “no-go zones” in European cities. He amplified the latter theme into a book.

Any Australian activist or leader who appears on the same stage as Kassam has clearly not reflected on the contribution that Islamophobic political commentary may have made to an Australian allegedly murdering 50 Muslims in Christchurch not five months ago.

Nor have they reflected on the fact that one of Kassam’s most frequent targets, London mayor Sadiq Khan, was also singled out by the Christchurch shooter in his manifesto.

Some of the politicians speaking at the event also represent fairly radical understandings of “conservatism”. US Representative Mark Meadows, of North Carolina, once vowed to send Barack Obama “home to Kenya”, echoing so-called “birther” conspiracy theories about the former president’s origins.

Michigan Representative Rashida Tlaib, a member of the “squad” of leftwing congresswomen of colour, bluntly accused Meadows of racism last February.

Matt Gaetz, who is listed on the website but mysteriously absent from the daily schedule, suggested ahead of last year’s midterm elections that a so-called “caravan” of migrants traveling through Mexico for the US border had been funded by George Soros.

Gaetz’s tweet came just before the Tree of Life synagogue shooting — some commentators suggested that Gaetz and others who spread such theories contributed to the atmosphere in which the murders took place.

The man Raheem Kassam advised, and who he eventually sought to replace as Ukip leader, Nigel Farage, has made a political career of attacking the UK Conservative party from the right on issues such as immigration, multiculturalism and the European Union. He is generally accorded responsibility for Brexit.

And home-grown spectacle Mark Latham sits for the radical rightwing party One Nation in NSW. Apart from his blustering, occasionally defamatory public pronouncements, Latham advocates for a suite of policies which are hostile to sexual and demographic minorities.

Latham’s bad ideas are legion. To pick some at random: he has proposed banning transgender identification, has called patriarchy a “fake theory”, has asserted without evidence an epidemic of “anti-white racism”, and infamously accused a Muslim journalist of “aiding and abetting terrorism”.

One Nation, the party he leads in the NSW parliament, has policies including a Trumpian travel ban, the effective end of refugee settlement for those who arrive in boats, and a whole raft of policies singling out Muslims.

The bigoted ideas expressed by some of those on the program are further legitimated when Australian conservatives effectively embrace them as their own.

Islamophobia, antisemitic conspiracy theories and anti-immigrant xenophobia are not only reprehensible in their own right, but they have factored into recent mass shootings in the United States and New Zealand, and they are tearing apart democracies around the world.

Does this bother the Liberals and media figures who have chosen to participate? It should certainly trouble their colleagues, and the rest of us.