When rumors surfaced that Justice Alito could retire in the near future, members of Congress were quick to assert their role in a potential confirmation process. Senator Thune said Republicans “would be prepared to confirm” a nominee.    Those rumors have since subsided. But we should not be fooled by that burst of activity. Congress is otherwise asleep at the wheel when it comes to its constitutional responsibility to serve as a check on the Supreme Court's power.   Today’s Court would be unrecognizable to America’s founders. For much of our nation’s history, the Court remained limited in its role and modest in its ambitions. The Roberts Court, by contrast, thrusts itself into the center of public controversies, taking big swings at landmark legislation and undermining fundamental rights . It does so with almost no accountability, either as an institution or for individual justices.…