The late Charles Krauthammer, renowned political theorist, commentator and friend to Fox News, spoke about the repercussions of the Kremlin's moves in the years following the Soviet Union's demise.

As Trey Yingst reported, Russo-Ukrainian tensions are intensifying as the Parliament voted to impose martial law and President Petro Poroshenko restricted access to the country from Russian citizens between the ages of 16 and 60 -- amid fears of an attempted takeover.

"Daily life in Crimea is gradually approaching a state of war," Yingst reported.

When Russia first laid claim to Crimea after a formal incursion -- though one not recognized as legitimate by the United States -- Krauthammer said Vladimir Putin was then in a "position to take over other parts of Ukraine if he wants."

Krauthammer said at the time that Russia's attempt to "grab Ukraine" via Crimea is part of a "means to reconstitute a mini Soviet Empire."

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He compared it to Adolf Hitler's invasion into the Sudetenland -- a predominantly German-speaking region of the modern-day Czech Republic and Slovakia -- a move the Nazi leader claimed was in response to popular demand.

"This is what all dictators do," Krauthammer said.

In 1986, when President Ronald Reagan was dealing with the actual Soviet Union, Krauthammer said the "Reagan Doctrine" was a "very significant shift in our history of containment and a new way to contain the Soviet Union."

Chris Wallace added on "Special Report" that the "Trump Doctrine" for dealing with NATO is more "transactional" than when Reagan was working with the treaty organization against the Soviets.

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