The government is invoking what is the "state secrets" defense to keep its bad acts out of the justice system and out of the public eye. Torture someone yesterday? Can't talk about it -- its a state secret. Spying illegally? Shhhh -- state secret. Kidnap the wrong guy and sneak him out of the country to be mistreated? Would love to clear up this little situation -- but it's a state secret.
In a democracy, when the system of checks and balances is disabled, so is the democracy.