"I know there is profound concern across Europe and the world that America is laying down the mantle of global leadership," the Arizona Republican said Friday. "I can only speak for myself, but I do not believe that is the message you will hear from all of the American leaders who cared enough to travel here to Munich this weekend.
"That is not the message you heard today from Secretary of Defense Jim Mattis," he said. "That is not the message you will hear from Vice President Mike Pence. That is not the message you will hear from Secretary of Homeland Security John Kelly. And that is certainly not the message you will hear tomorrow from our bipartisan congressional delegation."
McCain joined other world leaders at the Munich Security Conference to discuss foreign policy, trade, national security and other leading global issues. Some in the international community have wondered if a president who campaigned on "America First" would still prioritize the concerns of other countries -- including American allies.
With nationalism rising across Europe, McCain said questions about the future of the West's commitment to democratic principles should be taken seriously.
"My friends: In the four decades I have attended this conference, I cannot recall a year where its purpose was more necessary or more important," he said.
McCain said the conference would entertain the idea of whether "the West will survive."
"In recent years, this question would invite accusations of hyperbole and alarmism," he said. "Not this year. If ever there were a time to treat this question with a deadly seriousness, it is now."
The lawmaker said past national leaders who worked hard to prevent the spread of nationalism would be shocked at how prevalent it has become in global politics.
"What would [Ewald] von Kleist's generation say if they saw our world today? I fear that much about it would be all too familiar to them, and they would be alarmed by it," McCain said, referring to the founder of the security conference. "They would be alarmed by an increasing turn away from universal values and toward old ties of blood, and race, and sectarianism."
"They would be alarmed by the hardening resentment we see toward immigrants, and refugees, and minority groups, especially Muslims," he added.
McCain challenged the worldviews popular with the American president and his allies, saying previous generations would be surprised to see them become so normative.
"They would be alarmed by the growing inability, and even unwillingness, to separate truth from lies," he said. "They would be alarmed that more and more of our fellow citizens seem to be flirting with authoritarianism and romanticizing it as our moral equivalent.
But McCain discouraged attendees from despairing over the situation, saying they should have hope that America's democratic principles would triumph.
"Make no mistake, my friends: These are dangerous times, but you should not count America out, and we should not count each other out," he said. "We must be prudent, but we cannot wring our hands and wallow in self-doubt."
"We must appreciate the limits of our power, but we cannot allow ourselves to question the rightness and goodness of the West," McCain added.