It all goes back to the Civil War. The number of Americans renouncing their citizenship rose to a new record of 5,411 last year, up 26 percent from 2015, according to the latest government data. Why? It all goes back to the Civil War, and to a tax meant to deter potential draft dodgers from leaving the U.S. Today, the goal is to make sure that all of the income of U.S. citizens, whether they live and work in the U.S. or not, is reported to the Internal Revenue Service. The rules got trickier in 2010, when, in an effort to cut down on tax evasion, the Foreign Account Tax Compliance Act...