John McCain -- Sorry, Dennis Rodman Is No Super Spy

Dennis Rodman is no Jason Bourne -- and was NOT a government spy sent to North Korea to help free the American prisoners ... at least that's what John McCain wants you to think.

Of course, Rodman's been taking credit for helping to convince Kim Jong-un to release Kenneth Bae and Matthew Todd Miller -- saying he was lobbying hard on behalf of the U.S. during his basketball summit in the DPRK earlier this year.

But when McCain was asked if he believed The Worm ... McCain didn't exactly back the NBA legend.