From that Slate article:
I suspect the biggest impediment to enforcing these bans is political willSUVs are wildly popular, and it will take brave city and state officials to challenge the right of residents to use their own streets. (Of course, like a FedEx truck, heavy SUVs are allowed to use local roads for a few blocks if they have business therelike going to or from a house. But in general, they're supposed to take the shortest possible path between designated truck routes.)
'Nuff said about the practicality of the three-ton limit.
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