Some big-name members of Congress say Edward Snowden has done his country a grave disservice and endangered American lives by disclosing the National Security Agency's surveillance programs.

The American people aren't so sure.

A new CBS News poll shows just 30 percent of Americans think Snowden's leaks have weakened national security, while 60 percent say his disclosures either have no effect or will strengthen national security.

The poll suggests that while many congressional leaders are incensed at Snowden's leaks, regular Americans have yet to be convinced he has done much damage.

The poll made no mention of Snowden and was mostly conducted before members of Congress including Senate Intelligence Committee Chairman Dianne Feinstein (D-Calif.) and House Speaker John A. Boehner (R-Ohio) accused Snowden of treason.

But it suggests Feinstein's and Boehner's effort to convince the American people that Snowden's actions threatened national security is an uphill battle.