I think that there's a power in that [information through tweets and sound bites ]. There's also a danger, what generates a headline or stirs up a controversy and gets attention isn't the same as the process required to actually solve the problem.

It is legitimate for the Turks to try to defend themselves.

Over the past eight years, the United States has worked hard to deepen partnerships across the region and across South-east Asia in particular. We're now a part of the East Asia Summit and we have a strategic partnership with Asean. At the US-Asean Leaders Summit I hosted earlier this year in Sunnylands, California, we agreed to a set of principles that will shape the future peace and prosperity of the region, from promoting innovation and furthering economic integration to addressing transnational challenges like global health security and climate change.

Yes, this is hard. But there should be no question that the United States of America is stepping up to the plate. We recognize our role in creating this problem; we embrace our responsibility to combat it. We will do our part, and we will help developing nations do theirs. But we can only succeed in combating climate change if we are joined in this effort by every nation - developed and developing alike. Nobody gets a pass.

We cannot simply look to austerity as a strategy and it is incredibly important that the Greek people see improvements in their daily lives so that they can carry with them the hope that their lives will get better.

It's the reason why I am always interested in engaging in people who are pushing us and pushing against the status quo. But having been an activist, the only thing that I'm always encouraging activists to do is, once you have raised the issue, and even through controversial means, you have to come behind it with an agenda and the possibility of reconciliation if power meets your demands.

No challenge poses a greater threat to future generations than climate change.