It's been 20 years since the terrorist attacks on the U.S. on Sept. 11, 2001. Kelvin and Josh remember where they were, and what we've learned since.

Links

• Katie Spotz

• Steve Buscemi on WTF Podcast

• Tom Junod's Falling Man story

• Cal Fussman's 9/11 story

• Fooled by Randomness by Nassim Nicholas Taleb