CAMP SMITH, Hawaii, Aug. 13, 2012 – Nearly six decades after an armistice agreement established a cease-fire that ended the Korean War, maintaining the fragile peace there and ensuring South Korean and U.S. troops are prepared to respond to aggression remains a top priority for U.S. Pacific Command.

North Korea looms as the most pressing trouble spot in Pacom’s vast area of responsibility that spans half the globe, Navy Adm. Samuel J. Locklear III, the Pacom commander, told American Forces Press Service.

Locklear expressed concern about tenuous, unstable conditions stemming from North Korea’s new, relatively untested leader, Kim Jong Un, and North Korea’s pursuit of nuclear weapons in defiance of U.N. Security Council resolutions.

“If there is anything that keeps me awake at night, it’s that particular situation,” the admiral said. “We have to ensure that we maintain as much of a stable environment on the Korean peninsula as we can.”

Toward that end, Locklear relies heavily on the leadership of Army Gen. James D. Thurman, commander of Combined Forces Korea and U.S. Forces Korea, to ensure that South Korean and U.S. forces remain strong.

Traveling to South Korea to meet with Thurman and South Korean leaders shortly after assuming the top U.S. military post in the Asia-Pacific region in March, Locklear emphasized the importance of the U.S.-South Korean alliance in deterring aggression and maintaining security and stability.

Locklear offered assurance of the “unwaverable” U.S. commitment to the alliance.

Although tensions on the peninsula have ebbed and flowed since the signing of the armistice, North Korean provocations, coupled with uncertainty as the new leader took power, have remained relatively high in recent years, noted William McKinney, director of Locklear’s North Korea strategic focus group. The group of military and civilian experts, one of three “mini think tanks” within the Pacom staff, advises Locklear and his senior staff on the North Korean threat and plans for a U.S.-South Korean military response, if required.

McKinney, a retired foreign area officer who spent 15 years of his military service in South Korea, plus three years as the civilian U.S. representative for the Korea Energy Development Organization, expressed disappointment about the difficult stalemate that continues to characterize the peninsula.

“We’ve been [in] sort of [a] treading-water situation for quite some time with North Korea,” he told American Forces Press Service at the Pacom headquarters here.

There’s a common saying within McKinney’s strategic focus group. “We had to build a fence across the peninsula to fence out North Korea,” he said. “But regrettably, that has also fenced us out from North Korea. It was never intended to be a lasting division.”

Ultimately, McKinney said, the United States would love a unified Korean peninsula — but only, he emphasized, if it had “a democratically elected, free market-based government for all of the Korean people.”

In a perfect world, that unified Korea would be an ally to the United States and a source of regional stability, he added.

While acknowledging that it’s still too soon to know the impact of Kim’s leadership, McKinney admitted that some of the initial signs are worrisome.

A missile test conducted just months after he came to power defied North Korea’s agreement to a moratorium on missile testing in exchange for 240,000 tons of U.S. food aid. North Korea also has yet to return to the Six-Party Talks with the United States, China, Russia, Japan and South Korea aimed at getting North Korea to abandon its nuclear weapons program.

A nuclear-free Korean peninsula is critical, McKinney explained, because a nuclear-armed North Korea would upset the balance of power in the region. Making it particularly troubling, he said, is concern that a weak, even rogue North Korean state is ill-prepared to handle the challenges and responsibilities of possessing nuclear weapons.

The balance-of-power issue has dogged the Korean peninsula for the past 100 years as Japan, China and Russia all fought to control it, McKinney noted. And during that timeframe, the peninsula has been a primary battleground for four of the five wars in the Pacific: the Sino-Japanese War of 1894; the Russia-Japanese War of 1905; World War II; and the Korean War. At the signing of the Korean conflict’s armistice agreement on July 27, 1953, the United States had lost 37,000 military lives and suffered 92,000 wounded. And what happens on the Korean peninsula today remains critically important to the United States, McKinney said.

That’s not only because of the U.S. alliance with South Korea, he said, but also because the destabilizing balance-of-power situation hasn’t gone away and continues to affect the entire region.

McKinney said he’s been impressed by the growing professionalism of South Korea’s military, which has been operating side by side with 28,500 U.S. troops there to maintain the peace.

“Over the years, there is no question that the [South Korean] forces have strengthened themselves and become a more professional military — a military that has modern weaponry, knows how to use it and that has operated for the last 25 years or more in a combined command with the United States,” he said. “They have become, in all senses, a much more modern, professional military than they were 60 years ago.”

As South Korea prepares to assume wartime operational control of its forces from the United States in 2015 and the United States focuses on rebalancing its military to the Asia-Pacific region, McKinney said, he doesn’t expect many force-posture changes on the Korean peninsula.

“From the standpoint of balance, the United States has really never left the Korean peninsula,” he said. “We have never lessened the importance of our forces on the Korean peninsula [or] our commitment … to the alliance.”

But Locklear made clear while visiting South Korea that North Korea’s government has important decisions to make.

“Should the North Korean leadership choose to start abiding by its international obligations, to cease provocations, this would be a preferred path,” he told reporters in the South Korean capital of Seoul.

“But if further provocations is the path that they would continue to pursue,” he continued, “then the challenge for us is to ensure that our alliance remains strong, that we work closely together to monitor and share information, and that we have the proper procedures in place … [so] the security of the alliance is ensured.”