Well, not everyone here (or in the world) is from your country, mosgood...
But, I can appreciate your point that self-interest determines all positions. And that is the singlemost debilitating pressure limiting the legitimacy and potential good the UN could achieve.
Japan feels that since it pays 19.5% of the UN budget, it should have permanent member status and at least a little influence how, or where, it is spent. Only the U.S. pays more - 22%. That isn't much of a spread considering that the U.S. GDP is 50% larger and the population is double.
For the U.S., Japan permanent membership would result in a stronger position since Japan-American interests are more closely aligned than any other combination. The U.S. and Japan together are 50% of the global GDP. Economic strength used properly can tame an adversary or create an ally just as effectively as conflict.
The current lineup of UNSC membership and even the charter is woefully outdated and still reflects the world condition from the end of WWII through the cold war. Japan and Germany are technically considered to still be enemy states and the Soviet Union is still recognized by the UN charter.
Bringing about a reorganized UNSC with influence appropriate to current world conditions is the last best hope the UN has to exist and be potentially useful. I think a rational restructure of the UN should be explored because a legitimate, useful and meaningful UN is better than no world forum.
