Non-Islamic, non-foreign-motivated terrorist actions have killed at least as many Americans on American soil as those who were promoted by jihadists. But what we have also seen is ISIL evolve, because of the sophistication of their social media, to a point where they may be inspiring more attacks - even if they're self-initiated, even if they don't involve complex planning - than we would have seen some time ago.

One of the things I've learned about being president is that we'll work on issues for long periods of time, sometimes in obscurity.

But the question is, do we care enough? Do we care enough to keep standing up for the country that we know is possible, even if it's hard, and even if it's politically uncomfortable? Do we care enough to sustain the passion and the pressure to make our communities safer and our country safer? Do we care enough to do everything we can to spare other families the pain that is felt here today?

Get involved in an issue that you're passionate about. It almost doesn't matter what it is ... We give too much of our power away, to the professional politicians, to the lobbyists, to cynicism. And our democracy suffers as a result.

Let's be grateful for what we have. Let's be mindful of those who have less. Let's appreciate those who hold a special place in our lives, and make sure they know it. And let's think about those who can't spend the holiday with their loved ones - especially the members of our military serving overseas.

We have not always been in sync on every issue in terms of our core values, in terms of her integrity, her truthfulness, her thoughtfulness, [Angela Merkel] doing her homework, knowing her facts, her commitment to looking out for the interests of the German people first, but recognizing that part of good leadership on behalf of the nation requires engaging the world as a whole, and participating effectively in multilaterally institutions, I think she's been outstanding.

I am looking forward to getting out of the bubble. I am glad that I'm leaving this place at a relatively young age, at 55. So I have the opportunity for a second maybe even a third act in a way that I think would be tougher if I were, you know, the age of some presidents when they left.