okay 
arkhamrefugee asked me what excuse they gave and how I felt about elderly people continuing to drive, and minidoc asked me if they had even gotten out of the car to explain themselves and check on me. Yes, they did stop (eventually), and yes they did get out of the car to check on me (which took even longer). Now, here's the funny thing.What they said (the actual driver wouldn't say anything, her husband, the passenger, did all the talking) was that her shoes were wet (it had been raining earlier) and her foot slipped off the brake pedal. Again, let's assume they were going approximately 5 mi/hr, or 1.5 ft/sec, the whole time. From the edge of the sidewalk to my leg was about 6 feet. So from the point where she felt the tires hit the sidewalk to the point where she hit me, she had at least 3, maybe 4 seconds to either find the brake again, throw the car into park, pull the emergency brake, or (and here's the reprehensible part, that she didn't) at least hit the horn and give me a fighting chance to get out of the way. Not only did she not do any of these things, she still hadn't done them when the car came to a stop 5 or 6 feet later, when it slowly but steadily ran into a brick pillar on the front of the store.
What that says is that her reflexes are so bad that, when at all startled, she can't react to an unexpected hazard condition in less than 5 or 6 seconds. That is way too late. Which means that she is at least technically incompetent to be driving, because there are lots of things that can go wrong while driving that demand a lot faster response than that or you're going to kill some child, some other pedestrian, some motorist on the side of the road, some other driver, your passenger(s), and/or yourself. I think that someone who took that long to hit me, and yet hit me anyway, has no business driving.
I strongly considered calling the cops about it. But I knew that since I wasn't actually injured, the cops wouldn't do anything about it. Ironically, by not letting her break both my legs, I may have put the life of some kid that she's going to run over later at risk; after all, if I'd let her break my legs, she might have lost her license. There are laws in Missouri where you can lose your license if the courts decide that for medical reasons, you are no longer safe to drive. But those laws don't kick in until after your first serious accident.
The part of me that bends over backwards to be fair knows that there are plenty of people of all ages who have no business behind the wheel of a car, whose reflex times are just as bad as hers -- some 18 year old with a car full of friends distracting him, some 20 year old mother of 3 whose kids distract her at a bad time, some 25 year old yuppie who drops his cell phone on the highway and bends over to pick it up, some 40 year old security guard on a swing shift who's fighting to stay awake. And similarly, I've known mentally alert 80 year olds who could kick your butt in a judo match, whose driving is obviously not at issue here. "Unsafe to drive" really does have to be decided on a case by case basis.
But I will admit that a darker part of me was muttering all the way home about how much I'm going to hate the fact that, because of the huge numbers of people born between 1942 and 1960, for the next 20 years or so America is going to turn into a gerontocracy. The darker part of me wonders if my opposition to pharmaceutical research isn't also rooted at least in part in a grim wish that about half of the baby boomers, especially the better off half, would die a lot quicker than they're going to.