As I mentioned above I used to get flagged by US customs but I did get the SSSS when I went to Israel. They told me it was random but I didn't believe it. Once I faced Israeli security things got really crazy, like nothing I've ever experienced before. If you want to hear about that click my name and find my trip report. I understand the need for security but this was waaaayyy over the top.

I've always found the SSSS to be random. Spouse and I have had Global Entry and Trusted Traveler status almost since inception. I got the dreaded SSSS on 2 occasions when traveling back from the Caribbean back about 5 to 8 years ago. More recently (about 3 years ago) my spouse and about 30 others on our flight got the dreaded SSSS on a flight back from Europe (I thing it was Amsterdam). Anyway, about 20 minutes before boarding began she was called out at the departure gate and taken to a designated area for a "wanding" and hard search of her carry-on. The process took less than 5 minutes after which she was brought back to the gate area where she and I were given priority status and were one of the first passengers to board the plane. Nothing invasive or obtrusive and we benefited with being able to board the aircraft early. We've both flown domestically and internationally more than a dozen times since her most recent encounter without further scrutiny.