One of the most enduring mysteries of the final years of the Cold War was a period of great worry about nuclear conflict between the United States and Soviet Union. The “war scare” of 1983, which unfolded 30 years ago this month, is still shrouded in unknowns, but new information has come to light lately.

In March of that year, President Ronald Reagan called the Soviet Union an “evil empire.” Soon after, he announced the Strategic Defense Initiative, his “Star Wars” quest for a defense against ballistic missiles carrying nuclear warheads. In the summer, the United States carried out a provocative Pacific Ocean naval exercise aimed at the Soviet Union. On Sept. 1, the Soviets mistakenly shot down a Korean airliner, killing all 269 people aboard.

In this climate of tension, British intelligence received information from a spy in the KGB, Oleg Gordievsky, that Soviet leaders were growing paranoid about a possible attack. In early November 1983, NATO conducted a nuclear command post exercise in Europe, a simulation of preparations leading to war, known as Able Archer 83, which may have been misinterpreted by the Soviets as real preparation for an attack.

Recently, the National Security Archive at George Washington University published documents that offer insights about those tense days. The full story is not yet known, but the archives point toward a conclusion that the war scare was real.

It led Reagan to conclude, as he described in his diary and memoirs, that the Soviet leaders may have been more fearful of the West than he first realized. Reagan was rigid in his beliefs, but when circumstances presented him with new information, he changed. A few years later, Reagan negotiated the elimination of an entire class of nuclear-armed missiles with Soviet leader Mikhail Gorbachev.

His convictions were strong, but he was able to acknowledge change and recognize his own flawed assumptions. We could use some of that common sense.

The Washington Post (Nov. 19)