Charles Krauthammer said on "The O'Reilly Factor" tonight that Americans are feeling anxious and bewildered by the direction of the country, and some presidential candidates are capitalizing on that.

"We're getting kicked around in the world. We've got the Russians, we've got the Iranians kicking us around. ISIS spits in our eye. And economically, people have a sense that they are losing ground ... and they're looking for an explanation," Krauthammer explained.

He said that is why the "simplicity" of what presidential candidates like Bernie Sanders and Donald Trump have to say is catching on.

Krauthammer said that Sanders tells people all their problems can be blamed on the super-wealthy owning and controlling everything. He said that Trump's strategy, on the other hand, is to tell people that their leaders are stupid.

He said that type of rhetoric is what gets the initial wave of support, but it remains to be seen if that can last.

"Simplicity is not easy to maintain over time," Krauthammer said. "We'll see how it does."

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