It'll be interesting to see...
... if the US Armed Forces (and/or others) adopt the "crystal" for their medical corps: helmet flash, field ambulances, tents, etc. They've been using the red cross on a white field since at least WWII, and it's my understanding that it's the universal symbol in wartime for "Do Not Shoot".
Combat vets may tell me differently; i.e., that the red cross was no guarantee of safety under fire. But a military adoption, especially if it's widespread, will go a long way toward making it universal (see also: the inverted black V used to mark friendlies in Gulf War I and II).