With North Korea poised to conduct a seventh nuclear test, diplomacy remains at an impasse. 

Both Seoul and Washington have said the door to dialogue remains open without preconditions, but Pyongyang has shown little interest in stepping through.

A look back at efforts to arrange trilateral talks during the administration of U.S. President Jimmy Carter offers surprisingly relevant clues on how to get the diplomatic process moving again.

AN OPPORTUNITY ARISES

In the mid-1970s, the North Korean government began looking for ways to initiate dialogue with the U.S. A decline in military assistance from both China and the Soviet Union