What we have here, then, are three overlapping air defense identification zones -- of China, Japan and South Korea -- and three territorial disputes -- between China and Japan, China and South Korea, and Japan and South Korea.
And all three nations claim the right to fly warplanes into these zones, and to deny access to foreign warplanes.
America has little control over these countries, all of which have new governments that are increasingly nationalistic.
And this week there appeared an even more ominous cloud.
North Korea's 30-year-old ruler Kim Jong-un, who has been purging his party and army, ousted, on charges of corruption, his uncle and mentor Jang Song Thaek, the second-most powerful man in the regime.
Kim reportedly had two of Jang's aides executed, and he is now massing ships and planes along his western sea border with South Korea, a site of previous clashes between North and South.
Kim may also be about to conduct a fourth nuclear test.
Any collision between North and South could instantly involve the United States, which, 60 years after the end of the Korean War, still has 28,500 troops on the peninsula, with thousands right up on the Demilitarized Zone.
And, lest we forget, the United States has a 1951 security treaty with the Philippines that obliges us to come to the defense of those islands. Yet, Manila, too, is involved in a dispute over islets such as Mischief Reef and Scarborough Shoal in a South China Sea that has been declared sovereign territory by Beijing.
The U.S. security treaties with Manila and Tokyo were entered into to defend those countries against a Sino-Soviet bloc that no longer exists.
Our treaty with Seoul was signed when South Korea was ravaged and destitute after three years of war. Today, the South has twice the population and 40 times the economy of the North. Why are we still there?
Neither U.S. political party has shown the least interest in reviewing these open-ended war guarantees, though it seems certain that one of these 50- or 60-year-old commitments will one day drag us into a confrontation if not a major war.
U.S. foreign policy today appears rooted less in U.S. vital interests than in nostalgia for the Cold War. As Dean Acheson said of the British half a century ago, so, it seems to be true of us:
The Americans have lost an empire -- and not yet found a role.