Does the Obama administration know anything about world markets?

If Japan buys less Iranian oil and more oil from some place else, another country will buy more Iranian oil and less from that other place. There very little effect on anything. Possibly the only loss is presumably the oil went where it did to begin with because it minimized transportation costs.

On the other hand exempting 11 major countries from penalties for dealing with Iran's central bank means that any international transactions will be taken care of through those countries (in addition to China or Russia that would ignore the sanctions anyway). From Foreign Policy:

The State Department announced on Tuesday that it would exempt 10 European countries and Japan from penalties for doing business with Iran's central bank, because those countries are making significant progress toward weaning themselves off of Iranian oil.

"I am pleased to announce that an initial group of eleven countries has significantly reduced their volume of crude oil purchases from Iran -- Belgium, the Czech Republic, France, Germany, Greece, Italy, Japan, the Netherlands, Poland, Spain, and the United Kingdom. As a result, I will report to the Congress that sanctions pursuant to Section 1245 of the National Defense Authorization Act for 2012 (NDAA) will not apply to the financial institutions based in these countries, for a renewable period of 180 days," Secretary of State Hillary Clinton said in a Tuesday statement. "The actions taken by these countries were not easy. They had to rethink their energy needs at a critical time for the world economy and quickly begin to find alternatives to Iranian oil, which many had been reliant on for their energy needs."

The European Union banned all new purchases of Iranian crude oil as of Jan. 23 and will phase out existing contracts by July 1, Clinton said. Japan was able to reduce its dependence on Iranian oil even despite energy shortages created by the Fukushima nuclear disaster.

"We commend these countries for their actions and urge other nations that import oil from Iran to follow their example," said Clinton. "Diplomacy coupled with strong pressure can achieve the long-term solutions we seek and we will continue to work with our international partners to increase the pressure on Iran to meet its international obligations." . . .