Why America’s roads are so much more dangerous than Europe's

Updated by Norman Garrick, Carol Atkinson-Palombo, and Hamed Ahangari, Vox

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Where these strategies have been successfully implemented — New York City, Portland, Cambridge, and Seattle, along with Washington, DC — biking has skyrocketed and traffic fatality rates have dropped at a much higher rate than in other cities. Between 2000 and 2012, there has been a four-fold increase in the number of people biking to work in DC while the traffic fatality rate fell from 9 per 100,000 to 3 per 100,000. More research is needed, but one possible explanation is that protected bike lanes reduce the amount of space dedicated to cars and ultimately slow traffic.
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http://www.vox.com/the-big-idea/2016/11/30/13784520/roads-deaths-increase-safety-traffic-us