Of all the losses triggered by the meltdown of Bear Stearns Cos. a decade ago this week and the crisis that followed, perhaps the biggest was the public’s loss of trust in markets themselves.

No wonder so many investors have cowered on the sidelines of the bull market for the past nine years. Their faith in the ability of stock pickers to outperform has vaporized, saving for retirement often seems like a lost cause, and speculative temptations like bitcoin and other digital currencies can feel almost irresistible.

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