Taking action in time to prevent disaster has been difficult for the U.S. Our society wants to be left alone and never quite gives up the vain hope that other people and governments want the same thing for themselves. American foreign and domestic policy has often been inspired and shaped by calamitous events that could have been anticipated and possibly avoided.

Ronald Reagan's decision to invade Grenadato forestall human tragedy and further erosion of our influence in the Caribbean stands as one of those rare occasions when a President was able to act in time.

"The hardest thing in the world for a President is to see trouble coming-and then do something to prevent it," says Bill Hyland, former aide to Henry Kissinger and soon to be editor of Foreign Affairs. The short-run political risks can be immense. Even as powerful congressional Democrats were declaring Reagan's decision justified, the likes of Historian Arthur Schlesinger Jr. were scoffing at the invasion as unnecessary. There can be no final proof either way, at least now.

Franklin Roosevelt's efforts to get the U.S. prepared for war form a bright page in his history, but at the time they were bitterly opposed by many Americans who did not understand the approaching catastrophe. Dwight Eisenhower sent U-2 planes over the Soviet Union because he realized our first line of defense was information. When a U-2 was shot down in 1960, exposing the gigantic spy scheme, he was bitterly condemned by some for unnecessary provocation. The longer view now hails his foresight and courage.

For the most part, however, the record is not so happy. F.D.R. and his commanders did not move to prevent the Pearl Harbor debacle, though there was warning.  We knew about Japanese kamikaze pilots in World War 11. but we lost dozens of ships to suicide planes during the invasion of Okinawa. Hans Mark, a former Secretary of the Air Force who has analyzed these events, believes there is something in the American psyche that makes it difficult for our leaders to prepare for human behavior so far from our norms.

When the Bay of Pigs invasion began to falter, General Charles Cabell, deputy director of the CIA, called the President. He wanted U.S. airpower to blast Castro's tiny but effective air force from the sky. John Kennedy turned him down. Such a drastic step was beyond his ken. Some strategists still feel the invasion would have succeeded had Kennedy looked ahead and used more force.

The signals that hostages might be seized by revolutionaries in Iran were not properly weighed by Jimmy Carter and his aides. Marine officers in Beirut apparently did not give enough credence to the evidence available that terrorists might mount an attack with a truck full of high explosives, even if it meant blowing themselves up. Both events were too far from American experience.

The U.S. record is just as uneven in areas other than national security. Calvin Coolidge and Herbert Hoover have been castigated by historians for watching the signs of looming economic chaos in the 1920s and failing to take action that might have helped control the damage. The entire roster of modern problemscentral-city decay, environmental pollution, civil rights conflict-could be seen approaching, but no President really moved to head. them of

History's examples and recent events pose an intriguing question for Reagan's leadership. Can he see the trouble coming, from those predicted $200 billion annual federal deficits and, as in the case of Grenada, do something about them before they bring crisis'? The evidence of how all this red ink will affect our economy is mixed for the short run. But most thoughtful people are justly frightened by the long view. Failure to cope in time with the deficit problem could obliterate Reagan's Grenada success and mar his presidency. Prescient action could make history smile on him.