You might consider useful items that can be pressed into service as expedient weapons. I have, for instance, carried lanyards with a heavy carabineer on one end, and either my keys or a sturdy small flashlight on the other, through almost every flight I've taken in the last 18 years.
Braided paracord is very strong, and a 3 strand braid is wide enough to not burn you as it slips/flows through your hand. This is one of the most practical, low observability expedient distance creators you can have, but be advised, PRACTICE is mandatory. Before I carried the lanyard, I always wore a sturdy belt and had a padlock on my carry-on bag. In either case, you have useful items that can fill other roles unless you need to use them defensively.
John