From what I've already read and have been continuing to research, there are two major motions moving the markets today. Japan's yen was so heavily traded into USD for options and calls (and shorts), which now with their interest hike has them scrambling to cover the loans on foreign exchange. This is a big part of the selloff.<p>Secondly, there are swaths, and swaths, and swaths of debt that are due in short term, namely Q4 dependent (big lenders) and it is very unlikely they'll get paid. The credit markets are in shambles right now.<p>Good luck to all of us this is going to spread to all markets and due to US fear and panic, along with the political battles, this isn't going to end well any time soon.
One missed jobs report is a convenient reason, but I don't think that's it. Investors were upset the Fed didn't cut rates just before that report dropped, so they're doing a collective sell-off to force the Fed's hand.