Charles Krauthammer believes that President Donald Trump's inaugural address was the most "classically populist speech" we've ever heard from a U.S. president.

He explained that Trump spoke directly to his mixed, nonpartisan constituency, promising to be a president for all Americans.

"I think that will be be remembered as the 'Forgotten Man Speech,'" Krauthammer said.

He noted that Trump's cabinet, however, is more classically conservative, filled with people who will attempt to dismantle the entire legacy of President Obama.

"The president is not conservative in and of himself. He's more the populist, speaking against an establishment that's a bipartisan establishment," Krauthammer said. "But he's surrounded by a team and has an agenda - one item after another - that is classically conservative."

He noted that Bret Baier asked the Republican presidential candidates at the first primary debate if any of them would consider running as a third party candidate, and only Trump responded, "Yes."

"I think, after hearing this speech, we can conclude that Trump was a third party candidate who won under the GOP banner."

Krauthammer later addressed the implications of Trump's message to the world, saying our allies and trading partners are "quaking in their boots." 

"The way that Trump spoke about the outside world was the most aggressive, most hyper-nationalist and in some way, the most hostile of any inaugural address since the second World War. He drew a picture of a zero-sum world, where what we have done for the world, they have been stealing from us," said Krauthammer.

He said Trump's "America First" message is going to have a "huge effect around the world" as it becomes policy. 

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