When our founders created America, it was in the age of the printing press, when individuals could freely join the conversation. And that robust, democratic dialogue more often than not lifted up the best available evidence and asserted what was more likely to be true than not.

I think that we should ban so-called junk guns. I think we should ban assault weapons like the weapons used here [in Fort Worth], yes. I think that the kinds of weapons that have no legitimate use for hunting or the kind of weapon that a homeowner would use, I think they should be banned, yes, those kind of weapons.

The entire North Polar ice cap is disappearing before our very eyes. It's been the size of the continental United States for the last 3 million years and now 40 percent is gone and the rest of it is going.

CO2 is the exhaling breath of our civilization, literally... Changing that pattern requires a scope, a scale, a speed of change that is beyond what we have done in the past.

When you look at what has happened over the last few decades the natural fluctuations point in the opposite direction of what has actually occurred. When they run the models and plug in the man-made pollution, the correspondence is exact. Beyond that, the scale of natural fluctuations has now been far exceeded by the impact of man-made global warming.

As it turns out, the scientific community has been addressing this particular question for some time now and they say that increased heavy snowfalls are completely consistent with what they have been predicting as a consequence of man-made global warming.

When we respond to threats immediately and take action right away, it's usually the threats that we're hard-wired to respond to, the kinds of things that our ancestors survived.