Waves of enemy troops crested the horizon. The nervous young lieutenant turned to his trusted NCO and asked what they should do. “I don’t know about you,” replied the sergeant, “but I’m going to run like hell.”

The Korean Peninsula was home to one of the Cold War’s hottest conflicts. Combat raged for three years, and the Korean people have lived under a cold peace ever since.

Today, the situation in Northeast Asia is as dicey as any time since the 1953 armistice.

Kim Jong-un remains a top concern. Dear Leader III recently had his own uncle executed. Rumors that it was a death-by-dogs affair attracted all kinds of attention, until that story was traced to a Chinese satirist.

Though now debunked, the story remains troubling for two reasons. First, a lot of people found it quite plausible — showing how accustomed we are to expecting the worst from Pyongyang.

Second, even Korea “experts” can’t agree over what the killing means. Some think it shows Kim is effectively strengthening his control over the government and the military; others interpret it as an act of desperation, indicating Kim’s effort to consolidate power is flailing.

Either way, the experts expect more bad news from the world’s worst nation. Their predictions range from another nuclear test, to another attack on South Korea, to the regime imploding–dumping the country into civil war and throwing control of its nukes up for grabs.

As if that were not enough, Seoul’s “good old days” of worrying about just North Korea seem to be over.

South Korea is now caught up in China‘s latest round of rewriting international norms. Late last year, when Beijing expanded its Air Defense Identification Zone in the East China Sea, it included territory claimed by Seoul. That move sparked an angry response from the South Korean government.

Even more disturbing, however, is the abysmal collapse of relations between South Korea and Japan, our two most important Asian allies.

Last year, South Korea reacted strongly to remarks and acts by Prime Minister Shinzo Abe, who backtracked from Japan’s previous apology for invading Korea during World War II. South Korean apprehension rose again when Tokyo recently announced plans announced to upgrade its self-defense forces.

Lately, South Korean President Park Geun-hye has tried to dial down the anti-Japanese tone in Seoul, but public opinion polls are going the other way. Many South Koreans now rate Japan as a security threat on par with, or exceeding, North Korea or China.

Bizarrely, for once North Korea and the south are singing the same tune. North Korea’s ruling party newspaper, the Rodong Sinmun, labeled Abe a “militaristic maniac.” Some leaders in South Korea have even suggested the U.S. and China work to put pressure on Tokyo.

For U.S. foreign policy, this is a dangerous development.

Japan and South Korea are the anchor of American power and policy in Asia. Further, a solid relationship between these nations is the best guarantor of continued peace and stability in northeast Asia.

Both Japan and South Korea are strong, vibrant democracies. They should and must to come to terms with their troubled history. It would be a strategic blunder to let Pyongyang or Beijing think there is a gap between Tokyo, Seoul and Washington that they can exploit.

For its part, Washington needs to step up its efforts to show it will remain a strong regional and strategic presence. Expanding missile defenses, modernizing the U.S. nuclear arsenal and reversing the cuts in conventional force would go a long way toward reassuring our regional allies.

JAMES JAY CARAFANO, a Washington Examiner columnist, is vice president for defense and foreign policy studies at the Heritage Foundation.