Yet even without him, the CPAC agenda still features a number of speakers who have embraced the populist nationalism that propelled President Donald Trump’s campaign – but that is anathema to more traditional conservative values.

“At this point, what is conservatism in the age of Trump?” asked conservative writer and Trump critic David French, who in 2012 won CPAC’s Ronald Reagan Award but will not be attending this year.

“Because it’s starting to look an awful lot like just pure media criticism as opposed to the advancement of a coherent set of ideas grounded in the Constitution, centred around individual liberty, respect for life and strong national defence.

“This isn’t unique to CPAC,” he said, “but the conservative movement itself is in a state of flux right now, and the upheaval and turmoil you’ve seen over the Milo invitation and (it being) rescinded … is kind of a microcosm of that.”

Yiannopoulos is a provocateur who has a long record of making bigoted remarks, and has at times identified with the alt-right – a white nationalist movement. Plenty of conservatives thought that history should have disqualified him from an invitation in the first place.

He was perhaps Breitbart’s most controversial writer, before stepping down Tuesday after remarks surfaced in which he seemed to condone sex between “young boys” and “older men” – the same controversy that got him booted from CPAC.

“I am very relieved CPAC disinvited Milo,” said Al Cardenas, the former chairman of the American Conservative Union, which organises the event, in an email. He continued: “Breitbart News editor, he does not represent conservative values and is unacceptable as a CPAC guest speaker on a (number) of fronts.”

There will still, however, be a heavy Breitbart presence at the conference – the latest evidence of the provocative organisation’s influence in the Trump era. At last count, there were more Breitbart writers listed as CPAC speakers than US senators (likely due, in part, to the fact that CPAC falls during congressional recess).

Breitbart senior editor-at-large Joel Pollak, Breitbart London editor Raheem Kassam and conservative activist Sonnie Johnson – who notes her Breitbart affiliation in her Twitter profile – all appear on the programme. Ed Schultz, the MSNBC-turned-RT America host, the latter of which is funded by the Russian government, will also speak.

Meanwhile, Stephen Bannon, who is Trump’s chief strategist and previously headed Breitbart, will be in attendance and on a panel with White House chief of staff Reince Priebus. Bannon once described Breitbart as the “platform for the alt-right,” and the site is controversial even in conservative circles both for its attacks on Republican lawmakers and for coverage that has been criticised as bigoted and sexist.

CPAC organisers have made efforts to distinguish between the views of various speakers and those of what they see as belonging to the conservative movement more broadly. For example, Dan Schneider, the executive director of the American Conservative Union, will speak at a session Thursday morning titled “the alt-right ain’t right at all.” And ACU Chairman Matt Schlapp said in an interview that Yiannopoulos had communicated that he was not a member of the alt-right, and was only going to talk about free speech issues, had he appeared.

“There’s not room for groups that would advocate racism within the conservative movement, and we reject those who might say the alt-right comes from a conservative point of view,” Schlapp said. “We don’t think it does. We’re going to talk about that, as well. The conference is going to start with that, we’re going to hit it head on.”

But beyond that, he said, even as the American Conservative Union has core conservative principles, “CPAC is broad, it’s diverse, even though it’s conservative, there’s a lot of viewpoints, and we try as much as possible to bring people together from all factions of the legitimate conservative universe and let them have a role.”