I think it's very important to remember that so much of the work that gets done between countries is not done at the level of presidents, but is done within various agencies, whether it's law enforcement or economic ministries. And when they establish relationships and systems of communications and shared projects and shared visions, those structures continue even after any particular president is gone. It builds trust and understanding between countries that are critically important.

These kinds of tragedies [like shooting in Fort Lauderdale] have happened too often during the eight years that I've been president. The pain, the grief, the shock that they must be going through is enormous. I've asked me staff to reach out to the mayor down there and make sure that coordination between the state and local officials is what it should be. But I think we'll find out over the next 24 hours exactly how this happened and what motivated this individual.

Angela [Merkel] and I also agreed the need for a comprehensive and humane response to the devastating humanitarian crisis in Syria and for the influx of migrants and refugees from around the world. We need to build on the progress achieved at the U.N. Refugee Summit, which yielded new commitments from some 50 nations and organizations.

We're starting to make some progress. But there's still gonna be some pain out there. If I don't have this done in three years, then there's gonna be a one-term proposition.

We can lead this world and make it safer and more secure for our children and our grandchildren, for generations to come.

Many of our ideas of democracy, so much of our literature and philosophy and science can be traced back to roots right here in Athens.

I am a little jet lagged from my trip to Malaysia...The lengths we have to go to to get CNN coverage these days.