How One Tweet Almost Broke US Financial Markets

In the January/February issue of Mother Jones, I wrote about Wall Street's embrace of high-speed computer programs that execute thousands of trades per second. These algorithms, some of which can teach themselves and operate almost entirely without human interference, present a new and challenging danger to the stability of global financial markets because they work in timeframes that people can't begin to perceive. By the time an actual person realizes something is wrong, it might already be to...