With respect, you have it exactly backwards. It's the US, with its predominately low density, car-dominant building style that has vastly more traffic fatalities than higher-density Germany or Japan.
It's true that low-density SFH areas often seem more peaceful, but in practice cars there usually travel much faster than they do in higher-density neighborhoods, and it's speed that kills.
It's true that low-density SFH areas often seem more peaceful, but in practice cars there usually travel much faster than they do in higher-density neighborhoods, and it's speed that kills.