There is scientific evidence that demonstrates there is some impact from human activities. However I don't think the evidence is conclusive.

The best way to marginalize the Muslim Brotherhood [in Egypt] is in the ballot box, not through arrests and killing people.

Governor Romney is suffering from political amnesia.

In the midst of our wars in Iraq and Afghanistan, Putin invaded the Republic of Georgia. Let's call it for what it is. Here is Vladimir Putin with a failing Soviet franchise. And when he can't win the hearts and minds of his neighboring nations, he uses energy extortion, masked gunmen and barbed wire.

[Putin] is a bully. And bullies only understand when we punch them in the nose, but we need to do that economically.

In Maidan Square right now, you see thousands of Ukrainians protesting the Russian occupation of Crimea. So this is a Russian protest by Ukrainians who want their sovereignty. They want their freedom and they're protesting what Russia did in Crimea.

When we have an effort made at sanctions involving many other nations it has a potential of greater impact on Russia and discouraging Putin.