For four decades, the Korean Peninsula has been the site of a nearly static US policy, defined by some 37,000 American troops who guard the line between North and South.
But with a summit of the Koreas taking place this week in the North Korean capital, and the tantalizing prospect of an East Asian glasnost, the United States may need to consider some uneasy fallout from an otherwise positive development.
For one, a softening of North-South relations - which is still a long way coming - could make it difficult for the US to play the bad cop and keep North Korea's advanced weapons programs under check.
Likewise, if the state of military alertness along the so-called demilitarized zone is lowered, questions are sure to surface throughout the region and in Washington about why the US has some 100,000 troops in East Asia and the Pacific.
And finally, if North Korea were able to shed its "rogue state" image, the summit could help take the air out of one of the top US security priorities: national missile defense.
"It's hard to imagine a process of improving North-South relations that would not undermine current US arguments for such a system," says Joel Wit, the former State Department official who negotiated the 1994 Agreed Framework, which partially defines today's relationship between Pyongyang and Washington.
Already the Russians, who oppose the US missile-defense plan, are taking advantage of that argument. The Kremlin announced last week that President Vladimir Putin would visit North Korea in July, presumably to make President Kim Jong Il appear less threatening.
Up until now, the US rush to deploy a defensive missile shield has been driven by North Korea and its steady progress in developing a long-range missile that could one day reach US soil.
If North Korea became less threatening, however, defense planners could be forced to either slow the project or adjust it to focus on different threats.
As it stands now, for example, the national missile defense's first interceptor base would be in Alaska - a perfect place to defend against a launch from North Korea, but well out of position for an attack from the Persian Gulf.
In an alternate scenario, successful talks between North and South Korea have the potential to neglect the issue of Pyongyang's military, analysts say.
In the past, the North Koreans have used the threat of their huge military to win financial aid, and some analysts say they may try to do so again this week. Although they're lacking some resources, the North Korean armed forces have large amounts of artillery, more than 1 million active-duty soldiers, and 5 million reserves. That gives North Korea the fifth-largest armed forces in the world, and the border with South Korea is home to the world's largest military buildup.
Yet the summit is expected to focus on other topics, such as economic assistance and symbolic cross-border family visitations. Although South Korean officials have said they would bring up military concerns, they are unlikely to press the issue when other reconciliatory subjects are taking center stage.
The US, in turn, will need to work closely with South Korea and a third key player, Japan, to maintain a strong hand if relations in the region become less well-defined. "The summit could be the beginning of a process of change on the peninsula," says Mr. Wit, "and a situation of change is more difficult to manage."
Past US administrations have worked to limit outside financial assistance to North Korea. Recently, the US has shouldered economic aid - using it to encourage Pyongyang to ease its militant stance. But some analysts say successful talks could open North Korea to more aid, biting into US leverage.
"It does look to me as though the Japanese are now poised in a position where those aid flows could start on a considerable scale," said Paul Wolfowitz in a speech last week. Mr. Wolfowitz is one of the top foreign-policy advisers to Republican presidential candidate George W. Bush. "It might be the end of economic leverage."
Without that leverage, the US would be less able to monitor the North Korean missile program and nuclear program.
Under the Agreed Framework, North Korea said it would stop atomic development in exchange for US and Japanese help in creating new energy sources - in the form of two nuclear reactors that could not be used for weapons. US inspectors were allowed to visit a suspected North Korean nuclear-development site earlier in May, but found no evidence of ongoing work.
Yet suspicions remain. A 1999 congressional report says: "It is reasonable to assume that North Korea has made or could make a nuclear explosive device capable of producing a significant nuclear yield."
Finally, a successful summit could amplify questions that already exist about the large US presence in South Korea, and even Japan. While American troops are unpopular to some segments of South Korean society, the US considers them crucial to its global military balance.
"The North will pressure to get a commitment on US troops leaving South Korea," says Larry Wortzel, head of Asian studies for the Washington-based Heritage Foundation, "but I think the US is confident that [South Korean President] Kim Dae Jung will stand up on this issue."
Nearly half of America's forward-deployed troops are in the East Asia and Pacific theater. According the Donald Gregg, the US ambassador to South Korea from 1989 to 1993, the US may eventually be willing to cut those numbers, but not now.
"It's important for us to remain engaged in the Pacific and northeast Asia," he says. "We certainly need to have an air presence and an intelligence-gathering ability there, as well as the ability to build up from that."
(c) Copyright 2000. The Christian Science Publishing Society