Secondly, no, we are not going to lose 50% of our oil in one year.  But "a giant, global, vibrant free market" is in a way far more sensitive to smaller declines in oil supplies than was Cuba.  Once we are on the backside of the oil curve, we could see declines over 5% or more a year.  If this were the case, without adequate preparation, the results could be very serious.  

two points:

- the point about Cuba is that a command economy might be more capable of making a rapid adjustment to a change in its circumstances, than a more free market economy.  

There is precedent.  By any measure, the most successful economies in WWII at mobilising resources for war were the British and the Russian.  The latter was already a completely socialist state, and the former adopted total market socialism (rationing, the works) for the period of WWII-- so successful was Britain, that despite having a pre war economy only half the size of the Nazi one, and despite the brutal disruptions of the submarine war, in 1941 they managed to outproduce the Nazi economy in terms of total war production.  It was a stupendous feat, and, indeed, another part of Britain's 'finest hour'. (see Alan Milward, The World Economies 1939-45. Penguin Books).

- 50% drop in oil supplies is dramatic.  But it's not impossible.  It would take a serious blowup in the Middle East, but the world is on a very fragile supply line from Middle Eastern oil.  If someone found a way to close the mouth of the Gulf, and/or there was a revolution in Saudi Arabia, we would be well on the way to a 50% cut in supply.

Cuba made a dramatic shift.  If one believes the Peak Oil thesis, the whole western world will have to make that shift, albeit over a longer time period.

Such a time period may give time for the marketplace to work its magic, create new technologies and new sources of energy.  But we can't double the fuel efficiency of the US car fleet overnight for example.

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