(FORTUNE Magazine) – TO MERE taxpaying mortals, the dollars committed to Desert Storm look as awesome as the battle itself. Every time a cruise missile goes off, it's more than $1 million. Scud-busting Patriots cost some $600,000 each. Planes average $25 million. Even before missiles started flying, the desert operation had cost $10 billion. Forecasts are necessarily hazy, but the Administration figures the war could consume an additional $30 billion to $40 billion. The Congressional Budget Office estimates up to $86 billion for a war as long as six months with heavy losses (see chart). The final tab depends not just on the length of the war but on how much equipment is lost. In making its ''low'' estimate, the CBO assumed just one month, but a war lasting somewhat longer might cost no more if the fighting is light. Gargantuan figures indeed, but not scary in relation to the $2.5 trillion national debt. Certainly not scary enough to justify the taxes some Congressmen and economists want to impose. No one knows yet how much revenue would be needed, and any tax would trim private spending when the economy needs all the help it can get. Instead, we should borrow. Even if expenditures climbed to $100 billion, borrowing at 8% would cost the U.S. ''only'' $8 billion a year in interest. The American Enterprise Institute's Herbert Stein, who was President Nixon's chief economist from 1972 to 1974, calls that a ''trivial'' sum. Interest charges on the federal debt are marching toward a quarter trillion dollars a year. The U.S. is likely to pay considerably less than the war's total cost. Contributions from allies could reach $50 billion if all the countries deliver on their promises -- though some pledges remain in doubt. (Japan's recent $9 billion commitment, for example, has encountered sharp political opposition.) Moreover, the CBO numbers assume full replacement of major weapons and munitions. But since the government still plans to slim military spending, that's not probable. Lieutenant General (Ret.) Richard West, former budget director for the Army, expects that the U.S. will replace high-tech items like Patriots but not some older types of munitions. Even major weapons such as F-15s, F-16s, and M-1 tanks will probably not be extensively replaced. Instead, West says, programs for new weapons like the advanced tactical fighter and the M-1A2 tank will be accelerated. Since most of these new weapons would eventually have been delivered anyway, their full cost should not be attributed to Desert Storm. No war levy legislation is currently being written, but congressional calls for a tax debate stem from fears of another Vietnam, financially speaking. As Vietnam's costs escalated in the mid-1960s, Washington opted for butter as well as guns. That spurred rising inflation and interest rates, which eventually led to a surtax on personal and corporate income in 1968. But most economists outside Congress are in rare agreement that the worriers are misreading history. The Gulf war may last months, but it won't go on for years. Allies are helping foot the costs. And military stockpiles in the early 1960s were low, requiring large orders that overheated an economy already at full capacity. Brookings Institution senior fellow Charles Schultze, who was budget director during the Vietnam buildup, says the war's cost will be ''lower than many people believe,'' partly because the U.S. won't have to replace stockpiles of expendable weapons that were amassed to fight the Soviets. Like Stein, Schultze opposes a war tax now, though he would consider a temporary tax if costs escalated sharply. Tax fans argue that the U.S. should not foist yet another cost onto its grandchildren by adding to the federal debt. But as CRT Government Securities economist Mickey Levy argues, future generations should pay some of the costs since the benefits of a more secure world will accrue to them. What about paying for a postwar presence in the Middle East? General West doesn't foresee many American ground forces in the region, since the U.S. will want to keep a low political profile. More air or naval units might stay around, but the incremental costs would be relatively modest -- whether stationed in San Diego, Darmstadt, or Dhahran, they have to be housed and fed. Estimates of the costs and allied aid are written in sand because of huge military and political uncertainties. But unlike Vietnam, the financial issues are likely to be soon forgotten -- even if the final tally should turn out to be bigger than anything now foreseen. Compared with the overriding task of attaining stability in the Middle East, the dollar costs are small.

CHART: NOT AVAILABLE CREDIT: SOURCE: CONGRESSIONAL BUDGET OFFICE; FORTUNE ESTIMATES CAPTION: WAR'S ESTIMATED COST VS. DOMESTIC SPENDING