I think sometimes Europe may take for granted the extraordinary progress that's been made over the last 40, 50 years. I recognize that sometimes there is great frustration that arises out of the euro zone or out of the EU.

In 2010 there were a lot of folks who were still out of work. There were a lot of folks who had lost their homes or saw their home values plummet, their 401k's plummet.

What the Paris agreement now does is say to China and India and other countries that are potentially polluting, come on board. Let's work together so you guys do the same thing.

Based on current surveys of public opinion in the United States, it turns out that the majority of Americans think I've done a pretty good job.

If we choose only to expose ourselves to opinions and viewpoints that are in line to our own, we become more polarized, more set in our own ways. It will only reinforce and deepen the political divides in our country. But if we choose to actively seek out information that challenges our assumptions and beliefs, perhaps we can begin to understand where the people who disagree with us are coming from.

For decades, we've been told that it doesn't make economic sense to switch to renewable energy. Today, that's no longer true.

America can't provide health care to people who need it. We can't invest in science and technology, which will determine whether or not we are going to be competitive in the long term. There has never been a country on Earth that saw its economy decline and yet maintained its military superiority.