As the fall budget-crunching season approaches, the Army, Navy, Air Force and Marines have put aside their traditional rivalries to stand together in defense of full funding for the Air Force's favorite new jet, the F-22 fighter. The battle over the plane's supersonic capabilities and its supernumerary costs promises to absorb the Pentagon, Lockheed Martin Corp. and Congress. But underneath it all lies a much larger question: Is the U.S. military still building and buying weapons the way it did during the Cold War?

The basic problem, congressional critics and some defense analysts say, is that even in a time of uncontested U.S. military superiority, the Pentagon continues to develop ever more sophisticated and expensive weapons for large conventional battles instead of devoting greater resources to new missions, such as peacekeeping, and new threats, such as biological terrorism.

Both the Clinton administration and leading Republicans are calling for higher defense spending. But second thoughts about some big-ticket items have begun to grip even ardent defense supporters in Congress.

"There's no doubt that there are other weapon systems, already in the midst of the procurement process, that we ought to be looking at again," said Rep. Jerry Lewis (R-Calif.), chairman of the Appropriations defense subcommittee, who has led the move to delay F-22 production. "I'm not making a list per se, but I believe the Pentagon knows it's not going to be business as usual in the months ahead."

Lewis may not have a list, but it would be pretty easy for Congress to come up with one.

Take the Army's plans to buy more than 1,000 Crusader artillery systems for about $17 million apiece. At a time when U.S. ground forces are supposed to be getting lighter and more easily deployable, why is the Army building a 55-ton howitzer?

Or the Navy's planned fleet of $2 billion New Attack Submarines. With Moscow's once-menacing sub-building program virtually at a standstill, why is the United States embarking on another generation of underwater vessels?

Or the Pentagon's plans to spend $3.5 billion on nine new antiarmor weapons. Does the military really need more tank-killing armaments, given that U.S. inventories remain about as large as they were during the Cold War, and the threat of a massive Soviet tank assault on Western Europe has evaporated?

Defense Secretary William S. Cohen has acknowledged the need for a shift away from Cold War weaponry toward equipment designed for new kinds of warfare as well as peacekeeping and counterterrorist operations. But the Pentagon still concentrates on buying a few major weapons in large numbers, particularly the types of systems--supersonic jets, large warships and heavy weapons for ground units--that evolved during the 40-year standoff with the Soviet Union.

Pentagon officials justify new models of such weaponry as essential to maintain an edge over regional aggressors. The ability of Third World adversaries to produce high-tech weaponry, officials say, has been greatly enhanced by the ready availability of off-the-shelf gadgetry once possessed only by the military, such as night vision equipment, satellite-assisted locating systems and multi-spectrum communications gear.

Military commanders warn against rushing to the conclusion that the world has changed enough to dispense with tanks, submarines and fighter jets. Both Iraq and North Korea, the two countries that factor most frequently in U.S. military planning for regional conflicts, have large land armies with Soviet-style equipment.

"There is an emerging pattern that bothers me, that we're getting ourselves lulled into a sense of complacency, as we did after the Second World War," said Lt. Gen. Paul Kern, who oversees Army acquisitions. "We are not very good at predicting what the threats will be, but the world has proven to be not a very safe place."

Besides, defense officials say, much of the planned new surge in procurement--from $45 billion a year in 1997 to more than $68 billion by 2005--represents an effort to catch up after a decade-long "procurement holiday" in which military equipment purchases plummeted far more than other Pentagon accounts.

Still, there is a growing consensus within the defense community that the military may be planning to buy more than it can afford.

Notwithstanding commitments by both the White House and Congress to increase military spending over the next few years, many defense specialists doubt the extra money will materialize, given the prospect of large tax cuts. Pentagon projections, too, of big savings from more base closures and other efficiency measures are widely considered overly optimistic.

Moreover, various independent studies--including one in 1997 by a congressionally chartered blue-ribbon panel--have taken the Pentagon to task for failing to focus sufficiently on such emerging threats as terrorism, biological and chemical attack, and assaults on the nation's computer systems.

"The Pentagon and other groups are beginning to outline the new challenges, but we haven't identified ways in which we're going to go about meeting them," said Andrew Krepinevich, director of the Center for Strategic and Budgetary Assessments (CSBA), a Washington think tank that closely watches defense spending. "And yet we're moving ahead with major purchasing decisions. That's really putting the cart before the horse."

The rise in U.S. military procurement also runs counter to international trends. Economic troubles, for instance, have scuttled most of Russia's plans to upgrade military aircraft and naval systems. In January, Russian authorities faked the unveiling of a purported new stealth fighter meant to compete with the F-22, rolling out a plane that turned out to be an ordinary model built for testing engines.

"Most of the rest of the world appears to be spending substantially less on weapons procurement today than it was during the 1970s and 1980s," observed a recent CSBA report. "In 1997, the most recent year for which data are available, the value of arms deliveries to the Third World was only about 60 percent of its 1974-89 average."

The General Accounting Office, in a report last month criticizing the number of new antiarmor systems being financed by the Pentagon, noted that the number of tanks and other armored vehicles in potential conflict areas has fallen to less than 20 percent of what it was in 1990--when U.S. war plans still centered on defending against a massive land attack across Central Europe.

And yet, the Pentagon is spending $11.1 billion on 10 different antiarmor weapons now in production, plus $3.5 billion to develop nine new systems, including a lightweight, shoulder-fired weapon called the Predator; a launcher to sit atop a Humvee; and an antiarmor submunition that the military calls not just "smart" but "brilliant" because it uses acoustic and infrared seekers to home in on enemy vehicles from miles away.

"Plans to acquire large quantities of new and improved antiarmor weapons do not appear consistent with the reduced size of the armored threat and the existing large and capable inventory of antiarmor weapons," the GAO concluded in a report prepared for Lewis.

Rebutting those findings, George Schneiter, the Pentagon's director of strategic and tactical systems, complained that the GAO failed to account for the obsolescence of many stockpiled weapons. He said the new weapons would be more effective in piercing the latest kinds of armor and more precise in targeting enemy forces, helping to minimize U.S. and civilian casualties.

Another weapon struggling for justification is the Army's Crusader, a motorized, highly automated new cannon. Both the House and Senate Armed Services committees objected to it last year, contending that the weighty vehicle did not fit the Army's own plans for a more agile force.

Army authorities appear to have quelled the opposition for now. They say the weapon, which promises to move quickly across a battlefield despite its weight, will fire farther than existing howitzers and require smaller crews to operate. But many of the cannon's features involve technological firsts that are still being refined.

Too often, say some of the Pentagon's leading critics, the armed services are rushing weapons into production before confirming that critical technologies can work.

"The problem stems from letting some perceived threat drive everything," said Lou Rodrigues, who directs GAO studies of Pentagon acquisition programs. "By contrast, in commercial programs, knowledge of essential technologies becomes the driving factor. So, for instance, if you want to develop a plane with new avionics, you prove the avionics first because that's going to be a pacing element."

More than the Air Force and Army, the Navy is credited with maintaining a sense of economy and pragmatism in its modernization program. Last year, it scaled back plans for a new aircraft carrier design, opting to stay with the basic Nimitz-class model for now. And its New Attack Submarine represents a slower, smaller boat than the ill-fated Seawolf. The Navy is halving the size of its submarine fleet but says it still needs about 50 boats to conduct intelligence-gathering missions and other special operations around the world.

Nonetheless, at $1.9 billion a copy, even the revised attack submarine isn't cheap--a fact that Navy officials say reflects, in part, the collapsing economies of scale as production drops from about four boats a year to a planned rate of one or two.

And as cost becomes an increasingly important factor in the design of new weapons, the Cold War notion that U.S. weaponry needs to press the outer limits of technology is itself being called into question.

"This philosophy of going as fast as we can technologically," said Michael O'Hanlon, a defense specialist with the Brookings Institution, "that's the mentality we were in during the Cold War when we had a serious rival. But now that we don't, the question is: Can we make a conscious decision to slow down a little bit?"

There are other arguments, too, for slowing down. At a Senate Armed Services Committee meeting last month, Sen. Joseph I. Lieberman (D-Conn.) noted concern in some quarters that the technological dominance of U.S. weaponry might itself be destabilizing by inducing the Russians, Chinese and possibly others "to swagger, threaten [or] take precipitous action."

"It's an interesting theory, but the converse strikes me as rather absurd--that we should deliberately define superiority down," Defense Secretary Cohen replied. "The notion that we would somehow hold back and that we would allow others to catch up by our dumbing down our systems and not investing in the most sophisticated research and development and procurement . . . I think would be contrary to the national security interest of this country."

In Development: The Crusader

The Army wants to build 1,100 Crusader self-propelled howitzers at a cost of $22 billion*. They would replace Paladin artillery.

Weapon: 155mm howitzer

Range: 40+ km

Rate of fire: 10 rounds per minute

Resupply boom: Transfers up to 60 rounds of ammunition, fuel, lubricants and water to the self-propelled howitzer in less than 12 minutes.

Road speed: 67 km/hour

Cross-country speed: 48 km/hour

Cost: $16.7 million*

Deployment: 2005

Crew: 3

Cockpit is protected from nuclear, biological and chemical weapons.

* In 2005 dollars

SOURCE: United Defense