With any luck, the first casualty of this war will not be truth, but a longstanding falsehood: that war is good for the economy. Few may still subscribe to the Leninist doctrine that imperialism is the final stage of capitalism. But its Keynesian mutation, that wartime spending boosts growth through its contribution to aggregate demand, lives on.

''Was this war necessary to stimulate the ailing U.S. and other Western economies?'' asks a recent feature in the Toronto Star. ''Does industry thrive on the fates of the dead and wounded because capitalism requires constant growth and expansion? Is the system stuck in an endless cycle of depressions or recessions, wars, booms, then depression again until it is alleviated by expenditures on war?'' and so forth. Hint: Answers to all questions are the same.

So let's state this as clearly as we can: War is never good for capitalist economies. A successful conclusion to the war may, as U.S. Treasury Secretary Nicholas Brady has said, ''release significant energy into the economy,'' but that's only in comparison to letting the war drag on. It's the end of the war that's beneficial, not the war itself.

The lingering belief in the economic benefits of war rest on two confusions: between the short and long term, and between the special interest and the general. It also needs a heaping helping of historical revisionism. The legacy of war in this century, contrary to what you might have been reading, is unambiguously appalling in economic terms, from the introduction of the income tax in the First World War to the fiscal imbalances of the Reagan era.

The same people who believe the Second World War ended the Depression often also maintain Roosevelt's New Deal did the trick years earlier. Both cannot be true; in fact, neither is. The contraction in U.S. economic output stopped well before either could have any effect. The Depression did not end with the war, just as it did not begin with the crash. It began and ended as a monetary phenomenon: the implosion of the U.S. banking system in 1931, and the slow recovery in credit creation that eventually followed.

That is not to deny that economic growth quickened during the war - as it will in any period of inflationary finance. For there is no other way to call forth the production a fully mobilized war effort requires - The Second World War cost the U.S. $3.1 trillion in 1991 dollars, compared to the $86 billion worst-case estimate in the present example. The combination of inflationary money growth and price controls on consumer goods releases resources for the production of materiel in the short term. But suppressed inflation is hardly viable as a long-term economic strategy, as Mikhail Gorbachev is discovering.

It was all very well, moreover, for inflation to leap to 14% when prices were freed after the Second World War. Expectations then were formed in the knowledge that inflation had risen sharply after every war before then, and had always fallen just as quickly. Price stability could, therefore, be restored relatively painlessly. But the Vietnam war inflation offered no such assurance, once Nixon took the U.S. off the gold standard. We are still grappling with the economic consequences of that war today.

Perhaps the greater economic evil traceable to the Second World War lies in the realm of what is now called industrial policy, but was then called planning. The experience of wartime planning was instrumental in persuading large sections of British opinion, reflected in the election of the Attlee government, that the same model could be duplicated in peace. British thinking in turn heavily influenced postwar policy in North America.

Some still believe it. Clyde Prestowitz, a leading American advocate of industrial strategy, asks: ''Why can we make Patriot missiles and not VCRs? Because we want to.'' But no one doubts that American companies can make VCRs. The only question is whether anyone wants to buy them. Planning works for war economies because they have only one aim: to produce for the war effort. But the aims of a normal economy are as many, as varied, and as unpredictable as individual consumer wants.

Others point to the spinoff benefits of military research and development for the consumer economy, but you have to wonder if they're worth the investment. You can plot a fairly neat inverse correlation between the share of gross domestic product devoted to defence and the rate of productivity growth, with Japan at one end and the U.S. at the other. Of course, this may simply be an efficient international division of labor. Effectively, the U.S. is trading Patriots for VCRs: Japan finances U.S. military spending with the proceeds of its trade surplus, in return for the shelter of the U.S. defence umbrella. But given Pentagon cost structures, maybe the U.S. could get more VCRs if it traded something else.