This is because congestion has become a problem and they want to discourage them from utilizing this form of transportation. Over the long-term, this will create a change in habits by making public transportation and other alternatives economically viable. (Davenport) (Rosenthal) In the U.S., vehicles are a center of private transportation. This is because many cities were designed to accommodate cars. If there was a dramatic shift, these challenges could have an adverse impact on the auto industry, parts producers / suppliers and dealers. This would lead to a slowdown and possibly create a recession from a change in policies. (Davenport) (Rosenthal)

Moreover, the U.S. has not ratified and withdrew from the Kyoto Protocol. This means that they do not have to meet the same standards as Europe. To adjust for the increased amounts of traffic flow, there is a focus on using stop lights to effectively accommodate vehicles. (Davenport)...

is taking a much different policy approach by working to ensure that driving inside various cities is an enjoyable experience. This is achieved through controlling the flow of traffic to reduce gridlock. While the Europeans, want to make it difficult to drive in larger urban areas and have effectively banned many vehicles inside these locations. This is illustrating the distinctions in philosophy and approaches between the two. These views are showing that transportation is taking a much different focus. This is occurring with more of an emphasis on public transportation vs. automobiles in Europe. Whereas the U.S.; wants to avoid gridlock and control traffic patterns. (Davenport) (Rosenthal)
References

Davenport, John. The Ecology of Transportation. New York: Springer, 2006. Print.

Rosenthal, Elisabeth. "Across Europe." NY Times, 2011. Web. 5 Apr. 2014.