WASHINGTON - No one can sue the government over secret surveillance because, since it's secret, no one can prove his calls were intercepted, the Supreme Court ruled Tuesday, throwing out a constitutional challenge to the government's monitoring of international calls and emails.

The 5-4 decision is the latest of many that has shielded the government's anti-terrorism programs from court challenge, and a striking example of what civil libertarians call the Catch-22 rule that blocks challengers from collecting the evidence they need to proceed.

Over the past decade, the justices or lower-court judges have repeatedly killed or quietly ended lawsuits that sought to expose or contest anti-terrorism programs, including secret wiretapping, roundup arrests of immigrants from the Mideast and drone strikes that killed American citizens abroad.

The court's conservative majority believes that matters of national security and the fight against terrorism are properly decided by the president and Congress, not through lawsuits. They have erected procedural barriers to block such suits. The only exception has been lawsuits brought on behalf of the prisoners at Guantanamo Bay, Cuba, which have won new appeal rights for inmates.

The intense wiretapping of international electronic traffic began shortly after the attacks of Sept. 11, 2001. President George W. Bush was determined to detect secret terrorist plots, if possible, and ordered the National Security Agency to intercept calls and messages coming into and out of this country. Bush chose to bypass a special court created to oversee "foreign intelligence surveillance."

When Bush's order was revealed, civil libertarians called the mass surveillance unconstitutional. But Congress, with support of Democrats and Republicans, approved even broader electronic surveillance in 2008. By law, the targets of that surveillance must be outside the United States, but lawmakers conceded that calls and messages of some Americans would be inadvertently intercepted.