The topic of what to do if a person in a car is trying to run you down has come up a few times. I think
this recent event, documents just how far a car can travel with the driver incapacitated. To me this highlights why evasion is the best bet. I also think it is also a good reminder of maintaining awareness in all situations, as you can be vulnerable in a car.
This brings up the concerns of the latter situation. Using the framework of a car jacking, which I perceive to be the most likely attack for an average person. Even if you spot the potential threat approaching your car the option of reversing or going forward without endangering yourself and others may not be available. Furthermore, if you live in an area where roadside panhandlers are common, as I do, even if the option of forwarding or reversing is there, I would view it as not practical to take this measure every time a potential threat was near the car.
So what are some of the options? Considering that actions taken under real threat could be justified, ie running a red light at an empty intersection because some guy was approaching your car with a gun, whereas the threat may not fully apparent, and the same action because a panhandler approached your car would be hard to justify.