The Dow Jones Industrial Average has closed beneath 10,000 points for the first time since February 8. Despite trading above 10,000 for most of the day, the Dow began to falter around 2 pm, eventually closing at 9,974.45. The Dow first crossed the 10,000 point line in March 11, 1998. As Bill McBride puts it, "For investors this has already been a 'lost decade' and more." What happened and why?

• Market Volatility and Investor Uncertainty The New York Times quotes market strategist Joe Battipaglia, "It is hard to say if it is one bit of news or one development [causing the downturn]. But in the context of where investors want to be, there is no conviction on the short side or the long side. The market is stuck in a violent trading range of wide swings without any particular conviction and the market is now dominated by momentum trading." The Times also quotes another strategist Guy LeBas, "There is a very heightened degree of volatility. ... And we don't expect that volatility to go away any time soon."

• Too Much Bad News Salon's Andrew Leonard sighs, "Europe's woes, presaging a renewed global banking crisis, freezing up credit all over again, threaten to nullify all the good work that has been done. ... Throw in a possible war between North and South Korea, a recalcitrant environmental disaster in the Gulf of Mexico, and renewed signs of weakness in the housing market and it becomes impossible to avoid the feeling that a rough summer is ahead."

• The 'Rabid Bat' Market Daily Beast's Randall Lane dismisses the bear and bull. "What Wall Street, and business in general, abhors is uncertainty. And the results from Tuesday--indeed, from most of this month, starting with the May 6 'flash crash' which still hasn't been fully explained--resemble an animal pattern more akin to a rabid bat. Just look at the feeble factors driving the markets plummet on Tuesday: saber rattling in Korea and new debt problems for some of the European Union's sicker members. ... Wall Street would normally steamroll over such news." But it hasn't, because it is a rabid bat.

• Long-Term Market Instability Time's Stephen Gandel observes, "What is clear is that whatever direction we are headed, the captain has put on his fasten your seat belt sign. The stock market turbulence is actually a result of much bigger problems brewing than just the European debt crisis. So European bailout or not, big drops and jumps like today are here to stay." He gives three reasons: (1) "The first big thing that we are missing is average investors." (2) "China may be in a bubble as well. So Bye, bye global growth story." (3) "We have also lost the sense that stock deserves an equity premium."

• China Reconsidering Eurozone Debt Holdings  Calculated Risk's Bill McBride writes, "The euro was down under 1.22 dollars as investors apparently reacted to a story in the Financial Times: China reviews eurozone bond holdings. ... And this brought out the Dow 10K hats with the Dow closing at 9.974. Party likes it's 1998!"

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