Hungary’s nationalist leader, Viktor Orbán, will be the star speaker at an extraordinary session of America’s Conservative Political Action Conference (CPAC) to be held in Hungary this week, in an effort to cement bonds between the radical right on both sides of the Atlantic under the banner of the “great replacement” ideology. In a speech on Monday, Orbán made explicit reference to the ideology, which claims there is a liberal plot to dilute the white populations of the US and European countries through immigration. Increasingly widespread among US Republicans, the creed was cited by the killer who opened fire on Saturday in a supermarket in a predominantly black area of Buffalo, New York. Speaking in Buffalo on Tuesday, Joe Biden called it a “perverse ideology” and “a lie”. “I call on all Americans to reject the lie. I condemn those who spread the lie for power, political gain and for profit,” Biden said. “We’ve now seen too many times the deadly and destructive violence this ideology unleashes.” Orbán argued this week that the western world was “committing suicide” through immigration. “I see the great European population exchange as a suicidal attempt to replace the lack of European, Christian children with adults from other civilizations – migrants,” Orbán declared in a speech to mark the start of his fourth term in office. Echoing another popular theme on the American right, he argued that another form of cultural suicide was “gender madness”, a reference to the spread of LGBTQ+ rights in the west. The prime minister’s choice of vocabulary was not accidental, Hungarian political analysts said, but was rather designed to underline the common ties between his Fidesz party, his self-described “illiberal” form of government, and the American visitors arriving in Budapest for the first ever CPAC meeting in Europe. “I think it is logical that he was signaling to US conservatives because of the upcoming CPAC,” said Zoltán Lakner, a political analyst, and editor-in-chief of the Jelen news outlet. “He is trying to define himself as a global political actor, and at this point, he has kind of achieved that goal.” ​​One of the speakers of the event, Balazs Orbán, the prime minister’s political director, told the Guardian that “there are political forces in every country that see the world the same way” as Hungary does, but he said the US right wing has showed exceptional encouragement. “American conservatives are very supportive of us because they can see that we have huge domestic support and because they see Hungary as a conservative safe space,” Balazs Orbán said. Alongside prominent Fidesz figures will be an array of other European hard-right leaders, speakers will include the former head of the UK Independence party, Nigel Farage, Herbert Kickl, head of Austrian Freedom party, and Santiago Abascal, president of Spain’s Vox party. The US contingent will include several Republican members of Congress, Donald Trump’s former White House chief of staff, Mark Meadows, and the chairman of the American Conservative Union, Matt Schlapp. Most influential of all, the Fox News talkshow host Tucker Carlson will be addressing the conference, though he – like Meadows and Farage – will be participating virtually. Carlson has arguably done more than anyone to popularise the “great replacement theory” in the US, promoting it in 400 of his shows, according to an analysis by the New York Times. Carlson has developed particular ties with Orbán, originally through his father, Richard, whose political consultancy, Policy Impact Strategic Communications, has done lobbying work for the Hungarian government. Last year, Carlson broadcast a week’s episodes of his show from Hungary, with a soft interview with Orbán himself, putting both the prime minister and his government in a positive light, and glossing over EU complaints that Orbán has curbed independent media and judicial autonomy, enriched his associates from the public purse and reshaped election laws to his benefit. Earlier this year, Carlson produced another pro-Orbán programme called Hungary vs Soros: The Fight for Civilization, highlighting another ideological bond: the portrayal of George Soros, a Hungarian-born billionaire and philanthropist, as a malign Jewish financier pulling the strings on immigration and other liberal policies. “At this point, [American conservatives] are studying the Hungarian model and are looking at Hungary as a place where conservative policies can achieve their goals,” Boris Kálnoky, head of Mathias Corvinus Collegium (which was granted about $1.7bn by Orbán last year), told the Guardian. “Orbán is someone who attracts attention. And these visits by Tucker Carlson, who has a huge influence in this community, certainly put the spotlight on Hungary.” Richard Kraemer, a American Republican and analyst at the European Values Centre for Security Policy (EVCSP) in Prague, said he was concerned about the security implications of CPAC’s decision to hold its conference in Budapest which, after diplomatic expulsions in the rest of Europe following the Ukraine invasion, is widely seen as the most important outpost for Russian intelligence on the continent. “If you walk into this environment, you’re looking at – by at least one count –about a thousand security agency-related Russians that are in Hungary right now. And to put that in perspective, they have 170 diplomats in Washington,” said Kraemer, who co-authored a new EVCSP report this week that describes Orbán’s Hungary as “a Russia and China proxy weakening Europe”. “The are all these kinds of avenues whereby they’re able to put agents of influence in there and in front of Americans, who are basically low-hanging fruit that have decided to get even closer to the ground by showing up in Budapest,” Kraemer added. “What’s particularly disconcerting to me about this is that CPAC has basically decided that the cultural wars being fought right now by American conservatives are more important than America’s national security.”