The prices of crude oil and products are subject to much price arbitrage, which has the effect of encouraging the transportation of supplies from areas of relative surplus to those of relative shortage and of thereby containing local price spikes. This effect was most vividly demonstrated in 2003, when Venezuelan oil production was essentially shut down.
American refiners with unlimited access to world supplies were able to replace lost oil with diversions from Europe, Asia, and the Middle East. If North American natural gas markets are to function with the flexibility exhibited by oil, more extensive access to the vast world reserves of gas is required.