text: Not only not have a car makes you happy but it also can save the ecosystem. Green house gas is a big problem in the world now. Carbon dioxide slowly filling are planet. Acts like Vauban, and others like it, can influnce the world to change from the dangeruos road that we desided to take. But Europe produces 12 precent of green house gas, America on the other hand produces 50 precent of green house gas. America needs to change or we all die off.