One question before the Supreme Court this term was a big one: As technology evolves, how do our laws governing commerce evolve with it? The answer, issued in the ruling held in a 5-4 decision on Thursday, is a bad one for taxpayers. Many proponents of an online sales tax have argued that we must completely revisit what we know about interstate commerce, and create illusory tax regimes to contemplate a brave new order of online transactions. In reality, none of this is true. For one, while it has been 26 years since the Supreme Court visited the issue in...