Chancellor [Angela] Merkel is perhaps the only leader left among our closest allies that was there when I arrived. So in some ways we are now the veterans of many challenges over the last eight years.

I will not stand by while the special interests use the same old tactics to keep things exactly the way they are ... Not this time. Not now.

There's not a liberal America and a conservative America - there's the United States of America.

There's no doubt that I'm a better president now than when I first took office. This is not a job where there's a manual, and over time you get a better sense of what's important, what's not, how to see around corners and anticipate problems, as opposed to just managing problems once they've arrived.

The United States is committed to a regional order rooted in international rules and norms, including freedom of navigation, and the peaceful resolution of disputes. That's the only way to ensure our common security.

It's the answer told by lines that stretched around schools and churches in numbers this nation has never seen; by people who waited three hours and four hours, many for the very first time in their lives, because they believed that this time must be different, that their voice could be that difference.

For me, personally, the most difficult moments had to do with not just terrorist attacks, but also shootings.