Sure I think they are also interested in political blackmail, but I don't think they are interested in stopping the majority of criminals. I mean of the crimes that the NSA is interested in, I think terrorism and espionage top the list. I do think they are also interested in having control over the political system, and that certain targets may be blackmailed with information, but I don't think the NSA is going to gather communications of drug dealers and pipe them to the DEA in the name of fighting drug crime.