Democratic politics is a constant tug-of-war between principle and practicality. In a well-functioning system, legislators accept that fact and compromise accordingly; the electorate rewards them for maturity and realism. In the United States, however, democracy is not functioning particularly well at the moment. And so we have Sen. Ted Cruz of Texas.Many -- including, privately, many within his own party -- accuse Mr. Cruz, R, of grandstanding. Even accepting his objection to Obamacare as a matter of high conservative principle responsive to the wishes of his constituents, the course he has chosen, with his fellow freshman Mike Lee, R-Utah, and a handful of other senators, is patently futile and counterproductive.