In states like Wyoming there is an abundance of available land for development and many people there never give a second thought to the decrease in available living space. In countries like Japan, however, available surface area is at a premium, and entire underground communities such as Alice City have been planned.

Once the height of fashion in the cold war 60s, underground homes are again becoming a must-have item, and for much the same reason. This time the threat is global terrorism (and a slightly sticky situation between India and Pakistan).
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