It's not clear if we're noticing them more often, they're more often made public or the incidence is rising, but there have been numerous recent reports of motor vehicle accidents, fires, robberies and assaults involving wheelchair users.
With that in mind, what are some possible preventive measures? The best defense against strangers' attacks could be summarized as looking confident if not scary, and being mobile enough to wheel or drive quickly away from danger. We know wheelers who carry weapons, but have not seen evidence that they have prevented crime, and of course they have their own risks.
The vision and hearing needed to see a possible collision or other threat as quickly as possible are clearly key, as are the reflexes to swerve, stop, escape or duck. Portable lights and/or horns are both worth considering, depending on where and how you travel.
Overall, it doesn't seem like a stretch to say that when you're making the rounds in today's world, a very functional seating position would be a good thing to have. Let us know how we can help, and please be careful out there.