Never had my car seized. Not sure where you're going with that. Don't really care much about the natural disaster bit, most of us will be fortunate enough to never be in one. Public transport can only move so many people at a time too, so.. not sure about that either. Go to the 4th in Boston sometime and ride the subway after, it jams up every time.
The nation is too spread out for effective public transportation. The American Dream is owning a house in the suburbs. Those that don't want to deal with it, they live in the city and enjoy public transit. It's not what everyone wants out of life, there are always trade-offs. No "one size fits all".
Low speed limits and "traffic calming" measures lead to inattentive driving and road rage. I see it every day. All it takes is for one slow-poke to hold up a line of traffic and eventually the rules of the road go out the window. Accidents happen when people drive stupid, and limits that are so low almost no one obeys them, speed bumps/humps, road furniture, rumble strips, removal of passing lanes and such serve to make the roads inefficient and frustrating to drive on.
You know what would likely prevent a lot of accidents? Smarter traffic signals. Many towns have them programmed so poorly that people start to ignore them. Where do a lot of accidents happen? Controlled intersections. I love a good New England ice storm when it knocks out the power because some awful intersections actually perform better with the signals out.
Cars have enough safety features. Pave the crummy roads, take down half the signals and fix the other half to work more efficiently, and build more bike lanes. That's all I want. My car has more airbags than cup holders. I'm all set. If I want to communicate with another car I've got two fingers for that and a horn.