The Bush administration's blueprint to slash the armed forces by 25 percent in five years may no longer be prudent or even possible given the massive war preparations underway in the Persian Gulf, senior military officials said last week.

Many top strategists from the four services said they are frustrated and confused at being whipsawed between two conflicting sets of orders: to undertake the most radical shrinkage of the military since the Vietnam War ended, while also overseeing the most intense buildup of firepower since World War II.

Nearly a dozen senior officers interviewed agreed deep cuts should begin -- after the gulf crisis is resolved -- because of the diminished threat of a global war with the Soviet Union. But several questioned whether eradicating one-fourth of the military by 1995 -- a goal still in effect as a new budget cycle begins -- makes sense in light of Operation Desert Shield, the growing strength of regional powers such as Iraq, and the disquieting turmoil in Moscow.

Paramount among the concerns of these officers is fear that forces will be "hollowed out," that is, cut so precipitously as to badly damage training, leadership and other factors critical to combat effectiveness. The Army is a case in point. Now 740,000 strong, the Army was supposed to lose about 40,000 troops this fiscal year as part of an agreement with Congress to squeeze 80,000 from the four services, according to Pentagon officials.

Instead, the Army is growing by roughly 5,000 soldiers a month because of normal recruitment and a "stop-loss" order -- triggered by Desert Shield -- that blocks attrition through retirements and resignations. By the beginning of fiscal 1992 on Oct. 1, the service could face the immediate need to cut the 40,000 troops from this year, another 50,000 supposed to go in fiscal 1992 and the 40,000 or so retained under stop-loss.

Such an abrupt amputation, officers warn, could be devastating. "If I'm an Army commander," one Navy official said, "I've got a morale problem that's akin to what the Soviets are going through."

But Pentagon civilians say that barring a protracted war, the "glide path" for reducing the military by mid-decade must remain steady under the budget compromise reached in October. "Is there a lot of pain? There's a lot of pain -- a lot of structure and systems and plans and modernizing and other elements that are going to have to fall by the wayside," I. Lewis Libby, deputy undersecretary of defense for policy, said in an interview Friday.

Some analysts said they think modifications are inevitable, that it is unrealistic to expect the services to be "muscling up" for war in the gulf while simultaneously slimming down for the future. "It wouldn't surprise me if we found ourselves looking at a seven-year slope instead of a five-year slope," said Gordon Adams, a civilian analyst with the Defense Budget Project. Whether Congress -- already facing a $30 billion tab for Desert Shield -- will agree is unclear; a long-term U.S. military presence in the gulf, not to mention war, will further foul the Bush blueprint, an officer on the Joint Staff said.

For now, the services are drafting draconian cuts. The Navy, for example, foresees closing one-fifth of its installations worldwide in the next several years and "the outright burglarizing" of aircraft and ship procurement accounts in fiscal 1992 to pay for operating and manpower costs, according to a senior naval official.

The dilemma has its roots in a fundamental rethinking of the size and shape of the U.S. military that began in the Pentagon a year ago. The collapse of the Warsaw Pact and other factors rendered obsolete the central U.S. strategy of the previous four decades, a strategy to fight a major war in central Europe and rush 10 divisions of reinforcements across the Atlantic within 10 days. Last June, Gen. Colin L. Powell, chairman of the Joint Chiefs of Staff, and Defense Secretary Richard B. Cheney presented President Bush with a new strategic blueprint.

Their plan not only would cut 25 percent by 1995, but also shift the Pentagon focus to regional threats -- specifically including an Iraqi menace in the Persian Gulf. Powell proposed reorganizing the military into four "forces" -- an Atlantic force, intended to protect U.S. interests in Europe and the Persian Gulf; a Pacific force, stressing maritime power; a contingency force, for quick reaction to abrupt crises; and a strategic force to tend U.S. long-range nuclear weaponry.

Bush, under pressure from Congress to cut the deficit and acknowledge the new realities of East-West politics, concurred. The administration planned to promote the new strategy with a series of speeches and briefings in late summer that would begin with a Bush address in Colorado and a Pentagon briefing on Capitol Hill for leaders of the four congressional defense oversight committees. Those occurred on Aug. 2; by chance, Iraq invaded Kuwait the same day.

"The world's not the same as it was on the first of August. The basic difference is that we have expended an enormous amount of energy looking at the Middle East in the past five months," Maj. Gen. Charles A. May Jr., assistant deputy chief of staff for Air Force plans and operations, said Friday.

Although Desert Shield subsequently overwhelmed public discussion of the new strategy, that strategy remains the animating principle behind the Pentagon's long-range planning. In a speech in London on Dec. 5, Powell said, "Our view of where we were heading was clear and I believe is still clear." From a planning and budgetary standpoint, Desert Shield is "just a perturbation in the flow of events," Vice Adm. William D. Smith, the Navy's top program planner, said Friday.

The "flow of events" would, in five years, cut the Navy to about 450 ships, including 11 or 12 carriers, from today's 538 ships and 14 carriers; the Army would shrink to about 530,000 troops in 12 divisions, down from 740,000 in 18 divisions; the Air Force would drop from 36 wings -- typically with 72 planes per wing -- to about 25; and the Marine Corps would shrink from 193,700 to about 160,000 Marines.

Although there is widespread support in the Pentagon for the broad outlines of Powell's strategy, including the stress on regional threats, Desert Shield has stirred up considerable disagreement over how and when that strategy is best adopted.

Unquestionably, the services have, are and will continue to use the gulf crisis to justify themselves, including the need for higher "end strength," the total numbers of soldiers, sailors, Marines and airmen in each respective service. End strength in turn justifies "force structure," the organization of each service into battalions, squadrons, fleets and so forth. And force structure is tied to everything from how to fight -- doctrine -- to how many generals' and admirals' stars each service controls. Like many things in Washington, the issue involves power, influence, money.

The Marines, for example, believe that their quick, efficient deployment in Desert Shield helps justify their strategy of prepositioning $1.4 billion worth of equipment on 13 ships that cost $2 million a month each to operate, as well as the need for a force of at least 177,000 Marines in 1995.

The Army sees Desert Shield as reaffirming the need for "heavy" tank forces capable of destroying an armored enemy like Iraq. Many Navy officers believe the Army should also consider buying pre- positioned cargo ships; the Marines are wary of that because, as Marine Lt. Gen. Ernest T. Cook Jr., put it, "We don't think we need two Marine Corps"; the Army would prefer to have the Navy buy more "fast sealift" ships to move ground forces quickly, a proposal the Navy considers prohibitively expensive.

Beyond inter-service disagreements, however, the issue also involves genuine national security questions. The more lethal and competent a force, the greater the chance for military success and minimal casualties if a Desert Shield, in Pentagon vernacular, "goes hot." Insuring lethality and competence requires not just adequate force size, but also training, morale and many other factors, including the ability to conduct training exercises at distant points around the globe.

"You don't take a carrier battle group that's never been 200 miles outside the United States and all of a sudden put them in the Norwegian Sea," said Vice Adm. R. J. Kelly, deputy chief of naval operations for plans, policy and operations. "We don't take forces and put them in the Persian Gulf {for combat}, especially in the monsoon season, if they haven't been there before."

All services agree that Desert Shield, if conducted in 1995 under the current force reduction principles, would look considerably different. To provide comparable Army firepower, for example, the president would already have had to declare a partial -- and possibly a full -- national mobilization to tap individual reserves, officials said.

Several officers also cautioned against taking the current confrontation as a blueprint for all future crises. "What we we want to avoid," said Brig. Gen. Daniel W. Christman, the Amry's director of strategy, plans and policy, "is getting ourselves locked into the environment where Desert Shield is the planning paradigm for the next 20 years."

Staff researcher Lucy Shackelford contributed to this report.