President Reagan has been wrestling with history off and on throughout his political career, sometimes tripping over references to events that didn't happen quite the way he described them.

During his interview with CBS anchorman Walter Cronkite this week, Reagan appeared to draw a parallel between what he remembered as former president Franklin D. Roosevelt's call for a "quarantine" of Nazi Germany and the proper attitude for the world to take today toward the Soviet Union.

Cronkite didn't ask if Reagan really was calling for a qauarantine of the Soviet Union, so Reagan's exact intention is unclear. But for all practical purposes, Reagan's reference to Roosevelt invented a turning point in history that never happened.

According to Reagan, Roosevelt had suggested a course of action that might have prevented World War II. In 1938, Reagan said, Roosevelt "called on the free world to quarantine Nazi Germany, to stop all communication, all trade, all relations with them until they gave up that militaristic course and agreed to join with the free nations of the world in a search for peace.

"Can we honestly look back now and say that World War II would have taken place if we had done what he wanted us to do back in 1938? I think there's a very good chance it wouldn't have taken place," Reagan said.

There is a 100 percent chance that the speech he described never was delivered.

On Oct. 5, 1937, Roosevelt delivered what is known as his "Quarantine Speech." Nowhere in the speech does he refer to Germany. He makes no appeal for concerted "free wold" action to isolate Germany, and Roosevelt explained to reporters the next day that he had no program in mind to back up his rhetoric about a quarantine.

"It seems to be unfortunately true that the epidemic of world lawlessness is spreading," Roosevelt said in his speech. "When an epidemic of physical disease starts to spread, the community approves and joins in a quarantine of patients in order to protect the health of the community against the spread of the disease."

The speech ends with the words: "America hates war. America hopes for peace. Therefore, America actively engages in the search for peace."

When reporters pressed Roosevelt to elaborate on his mention of a quaratine, he refused. "Look, 'sanctions' is a terrible word to use," Roosevelt said at his news conference the day after the speech. He said the meaning of the speech was in its last words.

"I is an attitude, and it does not outline a program; but it says we are looking for a program," Roosevelt told to reporters.

Roosevelt's quarantine speech was made at a time when there was a fear of foreign involvement, similar to the nation's fears after Vietnam. Reagan, who was 26 when Roosevelt spoke, appeared to be remembering that as he told Cronkite that the Roosevelt speech had been strongly attacked in the United States.