Vermont recently became the latest in a series of states – including New York and California – to try and fail to implement a scheme to tax unrealized gains. There’s a compelling reason that even the most progressive states can’t generate any momentum for taxing unrealized gains: it’s pure guesswork. It involves taxing hypothetical income that doesn’t even exist for assets that haven’t been sold. Between the IRS and individuals, an unthinkable amount of time and resources would have to be devoted to creating systems for Americans to appraise their illiquid assets and for the IRS to then verify…