California's proposed wealth tax may command the spotlight, but a broader push by states to adopt so-called "millionaire taxes" could have a much larger impact on the nation's top earners. Currently, six states plus the District of Columbia have enacted some form of a millionaire tax, while seven more are actively considering proposals. Together, these 14 jurisdictions are home to more than half of the nation's millionaire earners, according to IRS data and a Financial Planning review of state legislation ...