Similarly, with friends and associates, in the old days it probably used to be easy. You worked for the CIA, you came from Des Moines and when you started hanging out with a bunch of Russians, people started to ask questions.
Nowadays, we know people from every country in the world. I have a thousand names on my phone, and some of them may have criminal records, for all I know. Some of them may have extreme views. Nowadays we have so many contacts. How and what do you do to look at your circle of friends to see whether you happen to hang out with a lot of people from ISIS, for example? What practically can you do to screen through the vast number of contacts to see if there's something of concern?
