The panel he spoke at was ominously titled "The End of the West as We Know It."
"In recent years, this question would invite accusations of hyperbole and alarmism; not this year," McCain said of the event's provocative title.
But McCain did not discuss any Russian provocations, military or otherwise. Without naming the president, he "systematically dismantled" Trump's "entire worldview," according to the Washington Post.
McCain spoke frankly about the people of the West embracing "old ties of blood and race and sectarianism," "hardening resentment" towards immigrants, displaying an "unwillingness to separate truth from lies," and flirting with and romanticizing authoritarianism, a system antithetical to the West.
While Russia has been shown to support populist movements and even corresponded with the Trump campaign during the election, McCain laid the blame on the people of Western democracies for "growing complacent," "giving up on the West," and fostering a "decadence" which leads to world orders failing.
"All of us must accept our share of the blame for these events," McCain said.
"They have no meaningful allies, so they seek to sow dissent among us and divide us from each other. They know that their power and influence are inferior to ours, so they seek to subvert us and erode our resolve to resist, and terrorize us into passivity," McCain said of non-Western, authoritarian powers like Russia and China.
"These are dangerous times, but you should not count America out," said McCain to applause.
Carlos Barria/Reuters
"We cannot allow ourselves to question the rightness and goodness of the West," said McCain in a clear shot at Trump and Vice President Mike Pence's refusal to say the West is morally superior to Russia.
But McCain blurred the clear line he drew between his pro-Western orthodoxy and Trump's new populism when he said that Pence and Trump appointee John Kelly would back him up with similar, pro-NATO, pro-democracy, pro-liberal values, pro-Western messages to the conference.
You can watch the full speech below: