Dan Rather

Last week, writing about North Korea's threat to test a nuclear weapon, your reporter made passing mention of "the Pacific Rim's potential for volatility." Now that North Korea has apparently followed through on this threat (debate remains about just how successful the test was), it might be a good time to take a closer look at just why this region could be such a dangerous one.

Let's start with North Korea itself. It at least appears that Kim Jong Il's bluster about having nuclear weapons has something behind it. Just as importantly, North Korea has missiles capable of hitting a target anywhere in Japan, and possibly much farther. North Korea also maintains the fourth-largest military in the world, and massive artillery capabilities, poised to rain destruction on the South Korean capital in the event of war.

China, meanwhile, has the world's largest armed forces in terms of personnel, and is engaged in a wide-ranging campaign to modernise its equipment. China also, of course, possesses a nuclear arsenal.

Japan maintains a sizable military, too, under the name of 'self-defence' forces. It is, as one might expect, a thoroughly modern fighting force. And despite constitutional and cultural restraints in the wake of World War II, Japan has been steadily enlarging its definition of just what 'self-defence' means. It might be worth noting that one of the major events driving this was a North Korean missile test over Japan that took place in 1998.

Nuclear weapon production

For decades, the region's major players have coexisted in relative stasis. If China is not an ideal nuclear state, neither has it used nuclear weapons. Japan, though it could produce a nuclear weapon in short order, has chosen not to, in large part due to the legacy of Hiroshima and Nagasaki. The Korean peninsula has remained in a state of stalemate since the end of the Korean War, and the issue of Taiwan has, despite sporadic bellicose talk on both sides, so far been left unresolved. An uneasy status quo has held on the potential flare-up points.

The North Korean nuclear test threatens to upend what balance remains in this equation. China, apparently shaken by North Korea's actions, may decide to further bulk up its military, and is all the more likely to do so if Japan beefs up its conventional forces or develops its nuclear capability. And in all these countries, military hardliners are likely to gain ground in their respective governments.

This, in its broadest outlines, is the arms race that experts have feared will result from the North Korean test. The thing about arms races is, they often result in those arms being used - a classic example being the Anglo-German battle for naval superiority at the turn of the 20th century that led, indirectly, to World War I ... which in turn led to the Second World War and the Cold War.

It's important to consider, too, the substantial military presence the U.S. has in this part of the world: more than 28,000 troops in South Korea; about 50,000 in Japan. And just this week, our government reiterated its commitment to treat an attack on either of these nations as an attack on the U.S.

In addition to long-standing enmities and territorial disputes, the nations of the Pacific Rim currently find themselves in a feverish competition for resources, a byproduct of huge economic growth. In recent years, this competition has been peaceful. But there is no guarantee that it will always be so, and anything - such as the events of this past week - that makes war more likely must be regarded as very dangerous indeed. The stakes are extremely high, and the risks go beyond even those of a despot with nuclear weapons.

Dan Rather is an American television broadcaster.