"A general risk-off mode predominates, the Fed meeting yesterday having been viewed as a crushing disappointment by equity markets, " said Chris Beauchamp, market analyst at IG.

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So, despite the improvement in the Japan situation on Friday and the declaration of a no-fly zone over Libya, traders decided to avoid the potential headline risk and went back to risk-off mode into the close.

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But because of the great work of law enforcement, National Guard, Coast Guard, making sure that folks were out in rescue mode rapidly, even in some cases at risk of their own lives, no lives were lost.

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If the risk of economic contraction has increased and the governments are in the mode of spending cuts, can the banks refinance themselves with their shares under severe selling pressure?

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And despite Google executive chairman Eric Schmidt's hope that "self-driving cars should become the predominant mode of transportation in our lifetime", it could be that even a small risk could be too much for some people to be comfortable removing the driver completely.

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