Americans who pick up the phone to call overseas have no way of knowing whether they’re on the modern-day equivalent of a party line. For that, they can blame the unwarranted expansion of U.S. antiterrorism surveillance in the wake of 9/11.

More than a decade after the terror attacks, the constitutionality of spying on untold numbers of likely innocent citizens – including by monitoring their email messages – has yet to be tested by the courts. Now, though, the Supreme Court could clear the way for that long-overdue legal review with a ruling granting citizens the right to challenge secret wiretapping of international calls and messages out of the plausible fear that their privacy rights are being breached.

The court agreed Monday to hear the case brought by Amnesty International, the American Civil Liberties Union, journalists and others who contend they’ve had to curtail completely legal overseas communications because of the massive wiretapping sweeps.

It was four years ago that Congress granted U.S. intelligence authorities broad powers to spy on citizens’ overseas contacts. Obama administration lawyers, as did those working for Bush, contend the plaintiffs cannot prove their privacy was violated. Before issuing its final ruling, the Supreme Court must sweep aside roadblocks put up to stop the constitutional review to which every action of the federal government should be subjected.

Of course, citizens shouldn’t have to wait to have their privacy rights restored. That’s a job for Congress when the 2008 Foreign Intelligence Surveillance Act comes up for renewal later this year.