There are a few Marines at my Air Guard unit and we make a point of wishing each other a happy birthday (I wrote it on the whiteboard in their break room since it’s the weekend and I’ll be gone next week to Guam). We do it because we’re Marines but I also get a kick out of how it pisses off the other people. Since I’ve been in this unit I’ve probably asked a few dozen people when the Air Force birthday is and not one has been able to name it though a few got the month right. No eprit de corps whatsoever.
