While the U.S. Air Force has long maintained that the F-22 would probably not be exported, because of the large number of classified technologies, that is about to change. The other, largely unspoken, reason for not exporting was the cost of the F-22. Selling for about $200 million each, there are few countries that afford this kind of stuff. Then there is Japan. Apparently there is some interest here. With the second largest economy on the planet, and the second largest defense budget, the Japanese are used to buying expensive aircraft. The Japanese F-2, which is based on the F-16, and uses a lot of licensed American technology, cost some $100 million per aircraft. Since the F-2 was basically an upgraded F-16, a $200 million F-22 looks pretty attractive. But that's only if the Japanese don't try to build the F-22 themselves. The major reason why the F-2 was so expensive was because the Japanese regard their defense budget as something of a public works program, and a nice way to keep troubled companies alive. The Japanese are not unique in this, but they take the process to a new level. The United States will be reluctant to export the manufacturing techniques that go into producing the F-22, especially to a manufacturing competitor like Japan. But you never know. Japan might be willing to buy Japanese made F-22s at a cost of half a billion dollars each.
Then again, maybe not. The Japanese are primarily concerned with defending themselves against China or North Korea. Being an island nation, Japan has put a lot of money into its air force and navy. The Japanese have long believed in the superiority of quality forces, and the F-22 would best anything the Chinese are likely to come up with for several decades.