The examination of the social networks of most U.S. citizens would be a very big waste of government money and would ultimately affect taxpayers. The search of most citizens wouldn't provide anything fruitful and most of what the NSA could derive from its own information can already be attained from the social networks themselves, which already track their users.
The NSA should not examine the social networks of its citizens. It has no right to look up everyones profile, even if it has the right intention. Doing so violates our freedom and personal privacy that we as Americans still have. Its seems that with each passing day the NSA finds out more about each and everyone of us, and this is a vilation of our freedom act.