North Korea is changing. That doesn't mean Kim Jong-un is mimicking Mikhail Gorbachev or even Deng Xiaoping, at least not yet. But it does increasingly appear that Kim intends to chart a more moderate course for his nation—that is, make it less threatening, though not more democratic.

The U.S. should help Kim pull his country back from seven decades of confrontation. Kim's apparent reasonableness may turn out to be fake, but it is in Washington's interest to create positive incentives for the North. If President Donald Trump can do it right—imagine a White House signing ceremony for a peace treaty with Kim, China's Xi Jinping, and South Korea's Moon Jae-in—a Nobel Peace Prize might just be within reach.