"It will be an optional data field to request social media identifiers to be used for vetting purposes, as well as applicant contact information,"
"Collecting social media data will enhance the existing investigative process and provide DHS [Department of Homeland Security] greater clarity and visibility to possible nefarious activity and connections by providing an additional tool set which analysts and investigators may use to better analyze and investigate the case."
But doesn't this require the bad guys™ to fill in your "optional" data fields? Who are, by definition, bad guys™ and so are less likely to provide that information. Which means the only info you have is on law abiding citizens.
Yeah, I know, they might not always be law abiding citizens, in which case you've got the jump on them.