A war with Iran would:

Global Guerrillas

• Cause an immediate energy shock. Oil prices shooting through $200 + a barrel. Lost production from Iran, Iraq, and most of the monarchies. A potential loss of 6-10 m barrels a day?
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• Global depression deepens. Prices over $150 cause immediate recessions. Higher than that, who knows? Usually, a slow down in economic activity reduces demand, however with peak oil (we hit the max the world could produce a couple of years ago) and lost production from the Middle East, that price could remain high even in the face of a deep, deep economic depression.
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• Networked Resilient Communities. Nobody is going to save you. You need to prepare by building or moving to a resilient community that produces most of the energy and food it needs to survive.