In recent weeks, the price of oil has climbed above $90 per barrel. As chaos spreads through the Arab world, we could soon see much worse. With these facts in mind, it is essential that U.S. policymakers act to protect the U.S. economy from this ever-worsening trend.

The likely impact of a new oil price rise is shown in the graph below, which compares oil prices (adjusted for inflation to 2010 dollars) to the U.S. unemployment rate from 1970 to the present. It can be seen that every oil price hike for the past four decades, including those in 1973, 1979, 1991, 2001, and 2008, was followed shortly afterwards by a dramatic rise in American unemployment.

The distress to American workers caused by such events is manifest, but the economic harm goes far beyond the impact on the unemployed themselves. A sustained oil price of $90 per barrel will add $480 billion to the U.S. balance of trade deficit. Furthermore, there is a direct and well-established relationship between unemployment rates and rates of mortgage defaults.

Thus the $130 per barrel oil shock of 2008 didn’t just throw 5 million Americans out of work, it made many of them default on their home payments, and thus destroyed the value of the mortgage-backed securities held by America’s banks. This, in turn, threatened a general collapse of the financial system, with a bailout bill for $800 billion sent to the taxpayers as a result. But that is not all. The destruction of spending power of the unemployed and the draining of funds from everyone else to meet the direct and indirect costs of high oil prices reduced consumer demand for products of every type, thereby wrecking retail sales and the industries that depend upon them.

Indeed, the world today is already in deep recession. Yet as a result of the systematic constriction of oil production by the Saudi-led OPEC oil cartel, petroleum prices today stand at over four times what they were in 2003.  This has imposed a tax increase on our economy of $500 billion per year, equal in economic burden to a 20 percent hike in income taxes, except that instead of the cash going to Uncle Sam, it will go to Uncle Saud and his lesser brethren.

These, however, are said to be our “friends.” As current events in Egypt should make clear, however, there is every chance that someday — perhaps soon — we could wake up and find that the world’s oil is under new management, even less concerned with our well-being than the gang in charge today.