realifedad, perhaps it's because I'm really just a shallow kind of guy but I don't usually drag one subject into another unrelated one, in this case, the political to the social. You may not believe this but I really like you, I just disagree with your political views and of course, you disagree with mine. I know that you mean well from the frame of reference life taught you.
Flagging is the use of a colored handkerchief protruding from a back pocket. The right or left pocket has a meaning and the colors have meanings.
For instance, a bottom who enjoyes anal sex would wear a navy blue handkerchief in their back right pocket. A top who enjoys anal sex would wear a navy blue handkerchief in their left back pocket. They meet and hey, maybe a hook up.
This virtually eliminates the guesswork out of the uncertainty factor. Even if a guy forgets which pocket and colors mean what preference it still communicates that the guy is probably gay or bi.
Here are a couple of links to help;