For over a decade, some of us have urged the United States to pull all U.S. troops off the peninsula.
Had we done so, we would not be in the middle of this crisis now.
South Korea is not inherently weaker than the North. It has twice the population, and its economy is 40 times as large. And the South has access to U.S. weapons superior to anything the North can acquire.
After Korea, Vietnam, Afghanistan and Iraq, as Robert Gates said, any defense secretary who recommends that America fight a new land war in Asia ought to have his head examined.
Why, then, are we still on the DMZ?
The long-run danger that has to be addressed is this: Kim Jong Un is about 30, and his life expectancy, absent a coup, is 40 or 50 years. Yet, within a few years, if he persists as he promises to do, he could have dozens of nuclear-armed missiles pointed at South Korea, Japan and Okinawa.
And if Pyongyang becomes a nuclear weapons state, it is difficult to see how Seoul and Tokyo will not be required to match its nuclear arsenal, as Pakistan felt compelled to match India's.
And a nuclear-armed South Korea or Japan would hardly be welcomed in Beijing.
What would China do? Some Chinese are urging Beijing to dump North Korea as an unreliable and uncontrollable ally that could drag them into war. Hard-liners are said to be urging China to stand by her longtime ally and buffer state.
Whatever comes of this crisis, U.S. policy, seemingly frozen in the 1950s, is in need of review. We cannot indefinitely be responsible for the defense of South Korea from an erratic dictator hell-bent on acquiring nuclear missiles.
In the near-term, even a conventional war on that most heavily armed border on earth, between South and North Korea, would be a calamity. To avert it, if necessary, Obama should pick up the phone, call North Korea and talk directly to Kim.
In a far graver crisis, perpetrated by Nikita Khrushchev in 1962, John F. Kennedy did not hesitate to communicate with the culprit.