It's not an attack on individual liberty to discourage driving through city design unless you also think big highways that you can't get through by walking / biking are also an attack on individual liberty.
Except there's a difference between "despite our best efforts, some large cities are inconvenient to drive in" and "we're intentionally making our city difficult to drive in in order to discourage people from driving because we believe in the myth of global warming"
I don't know if you'll be able to find ANYONE in ANY city who claims that highways were constructed specifically in order to try and get people to walk or bike less. Seems every major European city government official is more than willing to admit it in the opposite case, though.
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SmartMuffin - Because anything less would be uncivilized
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