Also, fairly major maintenance taking place (replacing tires, etc.) on active runways at major US airbases, with USAF Security Forces with M4s at low ready pointed at us. I was the only person on the plane with the authority to actually be there more than in-contact-with-plane.
The low level guys guarding planes probably didn't have the autonomy to put their weapons away while guarding. This is SOP for a lot of military activities. Your weapon is out and held at the ready. Any other position invites liability as you can't get up to aim quickly enough in a firefight.
