by Sharon Begley

About the author: Sharon Begley is a science reporter for Newsweek magazine.

To bomb New York’s World Trade Center in February 1993, the terrorists needed about 1,200 pounds of fuel oil and fertilizer. The mix was sufficient to kill six people and turn three levels of parking garage into a tangle of steel beams. To detonate an explosion in London’s financial district two months later, the Irish Republican Army (IRA) used a ton of fertilizer spiked with Semtex explosive. That blast killed one person and blew holes in a dozen buildings. With 1,750 pounds of diesel oil and fertilizer, eight men arrested in New York in June of 1993 figured they could destroy the Lincoln Tunnel and the United Nations.

A Real Nightmare

But as witches’ brews go, this is all pretty thin...