JPMorgan, chased; Justice, lawmakers vow action.

COLUMN: In our opinion

The $2 billion trading loss announced last week by JPMorgan Chase CEO and President Jamie Dimon sounds like a lot of money, and so it is. But it's also a little less than one-tenth of 1 percent of the company's estimated $2.3 trillion in assets, and won't do much to dent the company's profitability in 2012. The last thing Mr. Dimon's announcement should do is serve as an excuse for further government regulation, never mind a criminal probe.

But what amounts to a routine - if outsized - paper loss for one company in the financial sector has already become both.

Many politicians seemed to take their cues from a former economist for the International Monetary Fund, who told The Associated Press: "It just shows that they can't manage risk - and if JPMorgan can't, no one can." And Bloomberg financial news reported yesterday that the Justice Department has launched a criminal investigation into the loss.

The reality is that banks large and small manage risk every day, usually successfully, and Mr. Dimon is among the best at that game. JPMorgan weathered the 2008 financial crisis relatively well and paid back government loans ahead of time.

Of course, investors do make mistakes, and when they do, shareholders and investors pay the price. In this case, a small group of investors in a JPMorgan division in London erred badly, and Mr. Dimon has left no doubt the loss was the result of poor decisions, including taking on too much risk and having too little monitoring.

But capitalism is all about risks and rewards, and no regulation...