Rising demand for oil exposed Europe, and later America, to oil shocks - serious interruptions in supply. Like a pebble tossed into a pond, an oil shock creats ripples, or effects, felt everywhere.Oil shocks have two causes. The first is natural, because existing oil fields may not yield enough to satisfy demand. Scarcity results in higher prices for oil products, reducing our standard of living. Natural scarcity was not a problem in the world's major producing areas until recently.The second cause of oil shocks is political. Political shocks happen when governments of oil-producing countries reduce or halt supply to gain the upper hand in dealings with other governments. This is the case in the Middle East, where oil has often mixed with politics, religion, and blood. The reasons for this have shaped the history of recent times.