I don't know but it seems authentic, and there is precedent - I remember an FBI report that included 'defenders of the constitution' as threats. I just finished reading the report and its main targets are militia movements, so at first it seemed maybe the infowars article was over the top, but no - it is grouping people with the following characteristics as possible threats:
- supporters of third parties (specifically mentioned RP, Barr, and Baldwin)
- anti NWO
- anti Federal Reserve (the End the Fed protests specifically were mentioned)
- anticipation of US economic collapse
- uneasiness over possible Constitutional Conention
- anti North American Union
- opposed to Obama's civilian military core
- anti RFID
- believe in state sovereignty
- anti IRS ~ income tax
- anti illegal immigration
- uneasiness over possible marshal law
- display Gadsden Flag or Upside down US Flag
- watchers of Zeitgeist, America: Freedom to Fascism
Every one of those characteristics applies to me (except the flags but people on my digg network display them), and I'll bet at least 50% of the above applies to almost everyone here. This is how they are identifying possible threats.