WATCH: Vanderbilt professor breaks down 'massive escalation' of Russia-Ukraine conflict

NASHVILLE, Tenn. (WZTV) — A Vanderbilt University professor spoke with FOX 17 News to break down the ongoing tensions between Russia and Ukraine.

The Russian Foreign Ministry on Tuesday decided to evacuate Russian diplomatic personnel from Ukraine, pointing at threats it has received. The move follows Russia’s recognition of Ukraine’s rebel regions and the Russian parliament’s vote to grant President Vladimir Putin a permission to use military force in Ukraine.

Kathryn David specializes in the history of Soviet Ukraine and Russia. In an interview, she explains the current phase of conflict, which began in 2014 with the Russian annexation of Crimea.

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"The war has been ongoing for the past eight years," David said. "But it was really in the past few months when Russia decided to send over 100,000 troops to the border of Ukraine and began escalating their rhetoric about the need for Russia to have more of a presence in Ukraine."

David says Russia accused Ukraine of war crimes without any basis, which is when most people realized it's not "business as usual, but a massive escalation" of a Russian intervention.

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Russian lawmakers on Tuesday authorized President Vladimir Putin to use military force outside the country — a move that could presage a broader attack on Ukraine after the U.S. said an invasion was already underway there.

Watch the full interview with David below.

Prof. David's current book project, “One Ukraine, Under God,” examines how the officially atheist Soviet state used religious institutions to govern and transform its newly Soviet populations in western Ukraine during and after the Second World War.

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