[Moomoomoo309]

Better road design. Speed humps, trees on the sides of the road, narrower roads, all of which will make drivers slow down simply because of the design of the road itself. No one's speeding on narrow roads, they'd be too likely to hit something.

[shiroiushi]

How do you get people to adopt better road design? American drivers don't want this, and they'll vote against anyone who tries to push it (in most localities, not all).