A tentative move toward diplomacy over the confrontation with North Korea has begun, though that hardly means the tension is evaporating.

In a village on their heavily militarized border, North and South Korean officials opened talks Tuesday, ostensibly over possible North Korean participation in the coming South Korean Olympics. South Korea would like the talks to expand beyond that, toward finding broader ways to lower tensions.

But as just one sign of how fraught the situation remains, simply consider this: U.S. officials are quietly debating whether it’s possible to mount a limited military strike against North Korean sites without igniting an all-out war on the Korean Peninsula.

The idea is known as the “bloody nose” strategy: React to some nuclear or missile test with a targeted strike against a North Korean facility to bloody Pyongyang’s nose and illustrate the high price the regime could pay for its behavior. The hope would be to make that point without inciting a full-bore reprisal by North Korea.

It’s an enormously risky idea, and there is a debate among Trump administration officials about whether it is feasible. North Koreans have a vast array of artillery tubes pointed across the demilitarized zone at Seoul, the capital of South Korea, with which they could inflict thousands of casualties within minutes if they choose to unleash an all-out barrage.