Some technologies don't pan out; some companies fail. But I will not walk away from the promise of clean energy. ... I will not cede the wind or solar or battery industry to China or Germany because we refuse to make the same commitment here.

The government has to treat all citizens equally. I am a strong supporter not of a weak version of civil unions, but of a strong version, in which the rights that are conferred at the federal level to persons who are part of the same-sex union are compatible. When it comes to federal rights, the over 1,100 rights that right now are not being given to same-sex couples, I think that's unacceptable.

There are legitimate concerns and anxieties that the forces of globalisation are leaving too many people behind - and we have to take those concerns seriously and address them. But the answer isn't to turn inward and embrace protectionism. We can't just walk away from trade.

I want to reduce America's deficit by cutting spending that we don't need but also by asking the wealthy to do a little bit more so that we can invest in things like research and technology that are the key to a 21st century economy.

Iran's nuclear program . . . there was going to be a time limit . . .

Operation Iraqi Freedom is over, and the Iraqi people now have lead responsibility for the security of their country

We should be more modest in our belief that we can impose democracy on a country through military force.