Their biggest legal triumphs have involved courts overruling legislatures to overturn longstanding precedents. ... President Obama's recent remarks notwithstanding, it isn't as if the left wants a Supreme Court that consistently respects legislative majorities. The iconic decisions of The Warren Court, Roe vs. Wade, and efforts to extend marriage rights to gays are all premised on the notion that striking down popular laws is sometimes a worthy enterprise. Nor is the left going to champion fidelity to the text of the Constitution as it was understood at the time of the country's Founding. And as Lawrence v. Texas shows, liberals are comfortable celebrating when longstanding precedents are overturned (after strategic hunts by ideologically-driven activists for the perfect case). Thus the unavoidably tricky position in which Affordable Care Act defenders find themselves: liberal justices are going to keep "discovering rights" and expanding certain liberties in the future, rejecting originalism, the judgment of legislatures and at times even longstanding precedent. They'll keep advancing the idea that ours is a living constitution that adapts with the times. And those commitments undermine complaints they make about conservative justices discovering rights, expanding economic liberties, overruling legislators, and overturning precedents.