When you have a nation of 1.3B people, with about 1.1B people crammed into the land area of the US eastern seaboard from Maine to Washington DC, and when there are 166 cities with populations over 1M, while the US has only nine cities with populations over 1M, people don't have the luxury of thinking about personal space.

"Personal space" is a concept which only societies with low population densities can afford.

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