In today's column, Paul Krugman writes about Exxon Mobil and global warming:

Global warming emerged as a major public issue in the late 1980's. But at first there was considerable scientific uncertainty.

Over time, the accumulation of evidence removed much of that uncertainty. Climate experts still aren't sure how much hotter the world will get, and how fast. But there's now an overwhelming scientific consensus that the world is getting warmer, and that human activity is the cause. In 2004, an article in the journal Science that surveyed 928 papers on climate change published in peer-reviewed scientific journals found that "none of the papers disagreed with the consensus position."

To dismiss this consensus, you have to believe in a vast conspiracy to misinform the public that somehow embraces thousands of scientists around the world.

Many a wingnut feels those of us in the fact-filled world are simply alarmists when it comes to global warming, that we've banded together to concoct some grand, internet-based conspiracy. The fact is to dismiss the prevailing peer-reviewed evidence is to indulge in the mother-of-all conspiracy lunacy.