California progressives are pushing a wealth tax that would skim 5 percent of the assets of billionaires to cover the state government's fiscal gap. That is, it would hit billionaires to start—there's no telling who would come to be regarded as wealthy enough to be fleeced as the state's spending likely continues to outstrip its revenues. But before Californians proceed down the path of chasing high earners out of the state, they should consider the example of Swiss voters, who just rejected a billionaire tax of their own.
