The lack of any spare capacity in the global pipeline makes it difficult to solve such situations with sanctions; taking any oil off the market would, at this point, merely ignite an already explosive situation. The megatrends fueling the global supply shortage tend to feed on one another. Higher prices fuel the growing tendency of oil states like Russia and Venezuela to re-nationalize fields. That often leads to lower output, due to the inefficiency of most state oil companies, notes Sanford Bernstein analyst Ben Dell. The publicly traded companies have to go where they can. As fields in peaceful places (Alaska, the North Sea) are tapped out, the hunt for new oil has moved into conflict zones (Nigeria and Angola) or geologically extreme territory (Siberia, the deep sea). And while higher prices are already driving down energy consumption in rich nations, that drop does not offset the booming demand in emerging markets.
Some dry but good reading from Newsweek on the ramifications of everyone fighting over the same thing, i.e., everyone is going to fight over the same thing.
This is also why Iran is having such a fun time being in the position they are. That is, the world is both trying to cut them off to punish for the uranium enrichment and trying to open them up to exploit their oil, natty gas, and pipeline potential.