The suppressed story can now be told of a showdown in the Persian Gulf in the autumn of 1980 when the two superpowers maneuvered dangerously near the edge of war.

Now a new military confrontation is developing in the same place. Lest the lessons of 1980 be lost, here is the chilling story:

After the failed attempt in April 1980 to rescue American hostages from Iran, President Jimmy Carter began preparations for a second rescue mission. His national security adviser, Zbigniew Brzezinski, wanted a larger, punitive military assault.

In the strictest secrecy, intense preparations for a rescue raid began at training camps from Florida to California. Some elements of this scattered force began training under the code name "Positive Leap 80."

The same code name had been given to a military exercise conducted a few weeks earlier. This was intended to mislead the Soviets into thinking all references to "Positive Leap 80" had to do with nothing more than a training exercise. The Soviets were not fooled. It's now known that the KGB had laid hands on the Pentagon's secret codes and were deciphering its most sensitive messages.

But the National Security Agency also has the ability to intercept and decode secret Soviet intelligence cables. It was clear from these intercepted messages that the Soviets were fully aware of what was happening. They had advance warning of Carter's plans.

He went ahead, nevertheless, with the quiet deployment of a strike force primarily in Egypt and Israel. The Kremlin reacted by shifting personnel and materiel from Europe to the edge of Iran and deploying half of its forces in Afghanistan closer to the Iranian border.

The Soviet commanders also went through some menacing exercises. These were later described by the Joint Chiefs of Staff in a top-secret report: "In August 1980, an unusually long and complex General Staff-controlled command post exercise featuring a mock national Soviet invasion of Iran was held in the transborder area."

A nervous Carter asked the Defense Intelligence Agency to "study and report on possible Soviet military reactions to various scenarios in which the United States forces have invaded Iran."

Back came a warning that the U.S. action would likely lead to a nuclear confrontation. Somewhere en route to the president's desk, the nuclear reference was mysteriously removed from the DIA's secret response. But what remained was sobering enough; Carter was told that the Soviets could be expected to retaliate with a major air and ground assault.

The Soviet threat convinced Carter to abandon his October adventure. He called it off, the tensions cooled and the hostages eventually were freed.

Postscript: The evidence cited in this account, including classified documents, backs up the columns we wrote in August 1980, warning that Carter was preparing for an October action in Iran.

The White House issued a scathing denial, saying that "The allegation made by Jack Anderson is absolutely false."