It seems that unless something changes between now and June 12, President Donald J. Trump will hold a summit with North Korean dictator Kim Jong Un—giving the ultimate concession, a legitimizing meeting with the leader of the free world—for nothing in return.

That would be a diplomatic mistake of historic proportions. In fact, it would be far worse than the Iran nuclear deal or the policy mistakes other U.S. administrations have made on North Korea going back to 1950s.

For Kim Jong Un, a photo with a sitting American President depicting the two as equals, would help him cultivate an international environment much more favorable to doing business with his regime. Nations like China, Russia and Iran would feel embolden to work with Pyongyang, making the argument that if Trump can meet with Kim we can have ties with them too.

The maximum pressure campaign the Trump Administration has spent months building, would be dead the second the first picture of Trump and Kim hits Twitter.