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TechnologyNorth America

The Interstate Highway System

1956 – 1992

Seventy thousand kilometres of motorway, justified as defence

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In depth

American roads until the 1950s were mostly narrow highways running through every town along the way. Urban routes were repeatedly driven through Black neighbourhoods, often the very ones marked on the redlining maps, and tore them apart; resistance to this gave rise to the modern movement for community consultation in planning. The network moved freight from rail to road and made car dependence structural rather than chosen. It is also why American energy use per head diverges so sharply from European.

For children

The United States built a network of motorways across the whole country, the largest public works project in its history. It was justified by defence — the army had to be able to move quickly — but what really changed was where people lived and how goods moved.

Sources

  • Federal-Aid Highway Act (1956)
  • Rose & Mohl, Interstate: Highway Politics and Policy Since 1939 (2012)

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