Break away fasteners are a thing now. Line it with some Kevlar fibre and some good thermal insulation/fire resistance and you have an amazing utility device.

In public, it billows behind you, making you look dashing and heroic. When the shit hits the fan, instant bullet resistant cover for civilians. A way to shield them from the heat of a fire, or a small explosion. You could even use it offensively to tangle or deceive an opponent!