I’m going to go through a bit of arithmetic here, but it’s in the interest of answering an important question: just how unfair a burden of American military bases is imposed on Okinawa? If you’re math-averse, you can skip over it.
Opponents of the transfer and expansion of a U.S. Marine base from Futenma to the Henoko district of Nago City in Okinawa often cite the fact that Okinawa, with just 0.6% of Japan’s total area, accounts for 73.8% of the U.S. base presence in Japan (that is, the combined area of bases used exclusively by the U.S. military in Japan). These two figures, 0.6 and 73.8, testify to the unfair burden imposed on Okinawa for what is supposedly a benefit to Japan as a whole.
Map of U.S. Military Bases in Okinawa (from http://www.pref.okinawa.jp/site/chijiko/kichitai/25185.html)
But just how unfair? The burden military bases place on a region depends both on their combined area and on the region’s size. The greater the area, the greater the burden. The larger the region, the smaller the burden. So to measure the burden, we can use the density of bases per unit area.
Now, if the American base presence were distributed evenly throughout Japan, the base density in Okinawa would be the same as the density in the rest of Japan (for which I’ll use the imperfect term “mainland”). As a measure of the density in Okinawa, we can use the ratio of 73.8 and 0.6, which is 123. How about mainland Japan? First, the percentage of bases it hosts is 100 – 73.8, or 26.2%. Second, the mainland‘s percentage of Japan’s total area is 100 – 0.6, or 99.4%. To get the density of bases in mainland Japan we take the ratio of 26.2 and 99.4, and get about 0.2636.
Now, 123 is about 467 times 0.2636. So instead of equal densities, we find that Okinawa’s is 467 times that of mainland Japan. That is how unfair the burden of the American military presence is on Okinawa: almost 500 times the burden on the rest of Japan.
The central government in Tokyo evidently considers the level of base concentration on the mainland appropriate. But it rigidly opposes any action that would significantly reduce a burden on Okinawa 467 times that level. It’s as if Japan concentrated nuclear power stations 467 times as densely in Okinawa as it did everywhere else. Can anyone deny that this is a gross injustice?
The Pentagon claims that the Henoko base is part of a realignment intended to reduce the burden on Okinawa. But “burden” is too vague; by focusing instead on relative base densities, we can advance the debate. At the end of this realignment, bases will still be concentrated in Okinawa hundreds of times more densely than they are in the rest of Japan. Calling that a reduction in burden is an insult. Much, much more is needed – beginning with the abandonment of plans for the Henoko base.
[This article has been revised to improve clarity.]