We remember, we rebuild, we come back stronger.

If, technologically, it is possible to make an impenetrable device or system where the encryption is so strong that there's no key - there's no door at all - then how do we apprehend the child pornographer? How do we solve or disrupt a terrorist plot?

We do need to make sure that we have an orderly, lawful immigration process.

If you want to get at African American poverty, the income gap, wealth gap, achievement gap, that the most important thing is to make sure that the society as a whole does right by people who are poor, are working class, are aspiring to a better life for their kids.

One of the things that you learn, having been in this [President's] office for four years, is the old adage of Abraham Lincoln's. That with public opinion there's nothing you can't do and without public opinion there's very little you can get done.

I have seen, the desperation and disorder of the powerless: how it twists the lives of children on the streets of Jakarta or Nairobi in much the same way as it does the lives of children on Chicago 's South Side.

I've always viewed the Paris Agreement as a starting point. If you look at all the commitments that have been made by all the countries, it's still not sufficient to deal with the very dangerous situation we face. What it has done is that it created an architecture whereby as technology improves, as we find new clean sources of energy, as we make our economies more efficient, then gradually we can turn up the dial and improve the outcomes of Paris.