Sen. John McCain (R-AZ) joined Martha MacCallum today from Capitol Hill to weigh in on the tense situation in Ukraine. He pointed back to President Obama's stance on Russia in a 2012 presidential debate, when he mocked Mitt Romney for expressing concerns about the geopolitical threat posed by Vladimir Putin.

"The president said the Cold War's been over for 20 years. The president may believe that. Putin doesn't," said McCain, saying Putin believes Ukraine is "the crown jewel" in maintaining Russian control over the former Soviet states.

McCain said he worries about what Putin will do in eastern Ukraine, beyond Crimea, suggesting "provocateurs and others" will seek to undermine the new government in Kiev. He also pointed back to 2012 when Obama was caught on an open mic telling then-Russian President Dmitry Medvedev to let Putin know he would have "more flexibility" after that year's election.

"That's really not a statement of strength," said McCain, arguing that Obama sees Putin and Russia "as he wants it to be," ignoring the realities of Putin's actions over the years.

McCain believes that when Obama made the "red line" statement on Syria and then refused to intervene militarily last summer, it sent a negative signal to the rest of the world. He predicts that China will follow suit with "much more aggressive" actions toward the Senkaku Islands, which are the subject of a territorial dispute between China and Japan.

Watch the full interview above and for more on the Ukraine crisis check out Shepard Smith Reporting, live from Kiev, today at 3p ET.

Powerful analysis of the Ukraine Crisis on Fox News:

Palin on 'Hannity': ‘Putin Doesn’t Change His Stripes’

Bill O’Reilly on Putin: ‘Long Past Time to Deal With This Thug’

Krauthammer: Obama 'Is Living in a Fantasy World'

Rumsfeld: ‘It Is U.S. Weakness That Has Shaken the World’