What politicians do with their personal lives can give us insight into their character. And character matters. Some of the most important decisions politicians can ever face involve issues that weren't part of their campaign, and may not have even been anticipated (see our response to 9/11, though less extreme examples are much more common). Campaign policy positions are of no use in informing us how politicians might respond. For that, personal character is one of the best guides we have. And the personal lives of politicians tell us a lot about a politician's character. We now know, for example, that John Edwards is reckless. You may not care about his fidelity to his wife, but his willingness to take great risks for purely selfish and petty reasons should give anyone pause.
That doesn't mean that everything is fair game, though. It matters that Edwards cheated on his cancer-striken wife with a woman he may have been paying illegally with campaign funds. It doesn't matter what their preferred sexual position was. Furthermore, the actions of those close to a politician or candidate do not give us much insight into the candidate themselves. So children of politicians, for example, should not receive the kind of scrutiny that the politician themselves may rightly be subjected to.
