In the main, I agree. By the numbers, the Pareto-optimal strategy is to do whatever you can about lifestyle diseases and traffic accidents, and ignore everything else.

But, I have a devils'-advocate response to this prompt:

> There is no similar set of things you can do to similarly reduce your risk of being killed or injured by a motor vehicle.

One possibility is to move to one of the car-free places in the world, and do your best to stay inside it. ( http://en.wikipedia.org/wiki/List_of_car-free_places )

That's unrealistic for most people (and a bit trite), but you can approximate that extreme by minimizing your contact with cars. I think if you lived in a place like Manhattan or San Francisco, and walked and used transit, and only crossed the street on signal at major intersections, the odds of being involved in an accident would be extremely small. And anyone can minimize their time on the road, no matter where they are, by doing business by Internet, phone, or mail, and by chaining trips. All of the tactics for frugal driving aimed at reducing mileage, are also effective at reducing the risk of being in an accident.

Also, in "Effective Cycling," John Forester has an argument for why vehicular cycling is safer than it appears based on the raw statistics, which is similar to your analysis of gun safety. He argues that the overwhelming majority of car-on-bike accidents involve either unsupervised children or adult cyclists making egregious moving violations --- running red lights or traveling on the wrong side of the road. So, you can make cycling very safe for yourself, if not everyone, by following traffic rules and supervising children.