I like the idea. I recently ran across the Confederate Memorial tartan, which is in the same general theme. There are a bunch of tartans that commemorate events, why not campaigns?

As for appropriateness of wear, that debate has already happened with the clan tartans vs. general wear. I'm a Desert Storm vet, but others could wear it because they are honoring their father/friend/neighbor who was there.

Wearing a campaign kilt certainly makes a bigger statement than wearing a lapel pin.