I don't think they have a strike capability at present..
That may change rather quickly.
They've got a very impressive "defensive" assets, including aerial refueling capability, which will be upgraded later this year using a modified 767.
Missile-wise, the Japanese have a full-blown space program, which says they've got the technical know-how for accurate missiles; and they've got "defensive" concerns that reach all the way to Beijing and Pyongyang -- so their missiles would have commensurate range.
And they've pretty much said -- through the use of very strong hints -- that they've got nukes.