Charles Krauthammer sat down with Greta Van Susteren to discuss what is at stake in Ukraine, as Russian forces reportedly now move into the Crimea region. He criticized President Obama for remaining passive and "mute" as events occur, calling on the administration to make "some recognition of the stakes here."

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He described Putin as a "bully" and "a thug," pointing out that as a former KGB agent Putin feels that Ukraine belongs under Russian control.

"[Putin] has said publicly that the greatest calamity of the 20th century was the collapse of the Soviet Union, the Soviet empire. And he wants it back," said Krauthammer, saying that there are differences between the current U.S.-Russia face-off and the Cold War.

He applauded the Obama administration for supporting Ukraine with $1 billion in aid, but believes more might need to be done.

"If the Russians are going to be crude. ... If [Putin] applies raw pressure, military pressure, then at least the West has to stand up and say 'we're going to put a flotilla in the Black Sea, we're not going to allow this to happen,'" he said.

Watch the full discussion above, including Charles' thoughts on Americans' disappointment with Obama since the election.

And tonight, don't miss On the Record at 7p ET as Greta investigates the health problems among U.S. sailors who were sent to Japan after the devastating 2011 tsunami and Fukushima nuclear disaster.

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