Voters in Washington state sent a clear signal to Congress, if only the latter will listen: Tax hikes, even “just on the rich,” remain unpopular.

The Washington State Constitution features what amounts to a ban on state income taxes, but the Legislature and governor instituted a dubious workaround this year by creating a new, 7% capital gains tax while misleadingly categorizing it as an excise tax rather than one on income. The tax, a classic “soak the rich” levy, applies only to gains above $250,000.