Charles Krauthammer told viewers Friday on “Special Report with Bret Baier” that when it comes to Donald Trump’s presidential run, “Republicans have experienced the biggest ideological earthquake of a major party in our lifetime.”

Krauthammer cited comments by House Speaker Paul Ryan, R-Wis., on Thursday in which Ryan said he’s not yet prepared to support Trump.

“I think it’s true that there are tactical reasons for Ryan doing this to protect his members,” Krauthammer, a syndicated columnist and Fox News contributor, said.

“The more cynical comments have been about [Ryan] looking for his own run for 2020, in the future; he is trying to appease his donors. I think that is rubbish.”

“The Republicans have experienced the biggest ideological earthquake of a major party in our lifetime. Fifty, 60 years of conservatism has now yielded to a leader who is not a conservative, but who is a populist. That’s a big deal. And I think what the Ryan statement is… if the party is now going to be split between the leader, the populist, and the old-line conservatives… he wants to establish a center of power and a kind of home for the conservative wing,” Krauthammer said.