Korean quandary


North Korea’s neighbors and the United States are rattled by Pyongyang’s recent dire threats. The U.S. and South Korean response to them has been appropriately tough.

This week, North Korea said it will restart its long-closed plutonium reactor and increase its production of nuclear material. None of the interested parties knows how seriously to take the nation’s new young leader, Kim Jong Un. Media coverage of thousands of screaming troops and of Mr. Kim poring over a map with a phalanx of generals behind him invites ridicule.

Yet North Korea has undertaken aggressive, destructive action toward South Korea in the past. South Korea’s president, Park Geun-hye, promises decisive retaliation in response to any North Korean provocation.

To reassure South Korea, the United States is conducting a program of joint military exercises. It has added visits to the region by B-2 and B-52 bombers and F-22 fighters.

Other parties with a stake in the controversy include China, Japan, and Russia, who also are partners in apparently moribund six-party talks. China, annoyed at Pyongyang’s new posture, reportedly has bolstered its own forces on its border with North Korea. That seems scarcely necessary, because North Korea depends heavily on China for food and fuel.

North Korea’s fire and brimstone could be an effort by Mr. Kim to establish his credentials as his grandfather’s and father’s successor. It also could be an effort to extract more aid from South Korea, the United States, and other past benefactors, although threats of attack are an odd way to seek help.

At the worst, Mr. Kim could be preparing to take his country to war in an effort to consolidate his leadership. Meanwhile, he is waving nuclear weapons around, and the United States is responding with military counterthreats.

What is known of North Korea’s military capacity suggests it lacks the ability to attack U.S. military assets outside of South Korea and Japan. Still, the possibility that its leaders are dangerously homicidal must be guarded against.