North Korea continues along the nuclear path. A new report warns that Pyongyang could amass a nuclear arsenal as large as 100 weapons by 2020. That would make the North a significant regional power.

Washington has no realistic strategy to deal with the Democratic People’s Republic of Korea.

The Obama administration’s chief policy has been to reaffirm Washington’s defensive alliance with the South. Some 28,500 U.S. troops are on station, backed by conventional and nuclear forces elsewhere.

Some analysts look to more economic sanctions to stop a North Korea bomb. But neither China nor Russia is likely to approve new UN penalties. Additional U.S. sanctions alone aren’t likely to cause the North to surrender a program deemed essential to the regime’s international standing and domestic stability.

There also is the increasingly forlorn hope for negotiation. However, voluntary disarmament seems especially unlikely given the critical political role played by the military in Pyongyang.

Some policymakers look to Chinese pressure on the North as a panacea. But Beijing has yet to fully enforce existing sanctions. The People’s Republic of China is not inclined to take steps which might violently collapse the North Korean state.

But instead of attempting to micro-manage the region, Washington should leave the Korean Peninsula’s future up to the two Koreas and their neighbors.

The world has changed dramatically since the U.S. got involved in 1945. What happens in Pyongyang today is of vastly greater interest to others in the region than America.

Of course, a DPRK deploying nuclear-tipped intercontinental ballistic missiles theoretically could strike America. However, Pyongyang knows that attacking the U.S. would ensure that North Korea ceased to exist. And the ruling Kims always wanted their virgins in this world, not the next.

While the U.S. retains an interest in a stable Northeast Asia, even more so do the surrounding nations.

America’s defense guarantee has deformed South Korean policy. Today the ROK enjoys a GDP around 40 times that of the North, population twice as big, and vast technological and international lead. Yet the South has continued to underinvest in the military.

U.S. policy has had a similarly perverse effect on Japan. American military support has left Tokyo as a geopolitical dependent, vulnerable to its potentially aggressive neighbors, both North Korea and China.

Russia’s relations with the North dipped substantially after the end of the Cold War. Ties now are on the rise, though mostly because of the new “cool war” between Washington and Moscow than genuine Russian interest in North Korea.

North Korea is Northeast Asia’s biggest security problem. But it is not America’s security problem. The U.S. is overextended overseas and perpetually at war and risk of war because Washington insists on making virtually every other nation’s conflict America’s conflict. The Korean Peninsula should be left to the Koreas and their neighbors.