Whether Democrat or Republican, do you really want your private tax information leaked with impunity? On March 9, 2010, around 10 a.m., I announced my plans to run for senate representing Delaware. Later that same day, my office received a call from a reporter asking about my taxes. It’s since come out, after a halting and unenthusiastic investigation, that a Delaware Department of Revenue employee named David Smith accessed my records that day at approximately 2 p.m. — out of curiosity, he says. That these records ended up in the hands of the press is just a coincidence, the IRS...