Diplomacy between the United States and North Korea has gone through familiar cycles of long stagnation, followed by brief bursts of hope and then inevitable disappointment, typically after North Korea reneged. President Trump’s three predecessors each went through the cycle.

In October 1994, Bill Clinton concluded what was perhaps the most ambitious nuclear agreement ever reached between Washington and Pyongyang — called, appropriately, the Agreed Framework.

Under the deal, North Korea agreed to halt construction of two nuclear reactors that the United States believed would be used to produce fuel for a nuclear bomb. In return, the White House pledged to give North Korea two alternative nuclear power reactors that could not be used in a weapons program — as well as fuel to tide it over before the new reactors were ready.