This month marks the 40th anniversary of the beginning of World War II -- the greatest carnage in human history. World War II is more than something to remember for its own sake. It is especially worth reexamining in the shadow of a nuclear World War III, from which there might be no one left.

Many of the theories about war and the prevention of war that we hear today pay no attention whatever to facts or to history. We are told that we have to avoid an "arms race" or the stockpiling of dangerous weapons, and that negotiation of differences is the key to peace. It all sounds plausible, but is there any hard evidence that it is true?

The Western democracies all too successfully avoided an arms race in the decade preceding World War II. Britain, France and especially the United States let their military forces dwindle in size and deteriorate into obsolescence, while Germany, Italy and Japan built up enormous, modern military forces. The American army was reduced in size for four consecutive years in the 1930s, and its appropriations were literally cut in half in one year -- while Japan was invading Manchuria, Germany was rearming, and Mussolini was preparing to invade Ethiopia. The U.S. Army was only the 16th largest in the world -- behind Greece and Portugal.

Never was an arms race so successfully avoided.

Then as now, the implicit assumption behind "arms race" rhetoric has been that one side builds up only because the other side builds up. But Hitler built up his war machine while the West was channeling its resources into social programs, and Japan became a naval power in the Pacific while the United States was sinking its own warships as a contribution to world disarmament. In our own time, the proportion of the federal budget going to defense has been cut in half while the Soviets have built up a larger nuclear arsenal than the world has ever seen.

As for the stockpiling of dangerous weapons, we did so little of that before World War II that in the months after Pearl Harbor we had to use ships, guns and ammunition left over from World War I and even from the Spanish-American War. American soldiers fighting for their lives on Bataan found that most of their mortars and grenades were so old they would not go off. Our stockpile was dangerous only in its ineffectiveness.

The implicit assumption behind the "dangerous stockpile" theory is that somehow it may go off, or cause war, by itself. But no nuclear bomb has ever gone off accidently; it would be hard to conceal if it did. People still cause wars. Weakness has invited wars far more often than strength, from the fall of the Roman Empire to the fall of Western democracies as Hitler rampaged through Europe in World War II. As our underground missile sites become obsolete sitting ducks for new Soviet missiles, the danger of war increases rather than decreases.

Finally, there is the panacea of negotiations and treaties as the way to prevent war. Plausible as this may seem, the facts just do not support it. The Western democracies were constantly negotiating with their adversaries in the years preceding World War II. The West negotiated away its own advantages and principles, one after the other -- and almost negotiated away its survival. The United States was negotiating with the Japanese when they attacked Pearl Harbor.

Wars don't just happen because there hasn't been enough talk, but because one side sees that the other side is all talk.

This is all the more likely when unequal terms are intransigently insisted upon by one side, and the other "realistically" accepts this as a "fact of life" to which it must adjust. Hitler was a master of this tactic, and the Soviets and the Chinese are no slouches either.

There are other ominous parallels between the conditions that produced World War II and conditions today. Perhaps the most important is that the West has lacked the will, even when it has had the power. In the early years of the Nazi regime, the Western nations had overwhelming military superiority. But Hitler shrewdly tested their will, with a gradually escalating series of treaty violations and aggressions. The West's repeated yielding only led to bolder demands and more ruthless actions, until a point was reached where the West was finally forced to resist, even with the odds perilously against it.

The American military superiority in the first two decades after World War II was equally overwhelming. Yet the will has been noticeably declining in recent years, as the United States has backed down in confrontations with petty dictators who have seized our people in Uganda, or our ships on the high seas, or threatened our canal in Panama. We have taken China's insistence on our severing diplomatic relations with Taiwan as a "fact of life" to which we had to adjust.

Part of this has been a war-weariness growing out of Vietnam, just as the West in the 1930s was still war weary from the devastation of World War I. But along with this is the economic reality that military spending competes with spending on programs with more obvious and immediate political payoff. Both then and now, we have treated social experiments as a necessity, and survival as a luxury.