Of course with most national flags you can't fly them upside down as a distress signal, because they look just the same either way up. The countries concerned seem to get by without having that facility.

I was reading a stiry about how most flags these days are made in China, and they have to step up the production line when countries do something that makes people inclined to burn them. Stars and Stripes and Union Jacks are big sellers in that respect.