U.S. Prepares to Test a Reservist-Backed Military : Mobilization: The nation increasingly is dependent on reserves to fill gaps in wide-ranging specialties.

John Metzger, fresh from his studies as a graduate student at Utah State University, was eager to start a new career as a quality-control chemist when trouble flared in the Middle East.

Now, when he reports Monday for his first day at DataChem Laboratory, an environmental testing firm in Salt Lake City, he will inform his new boss that he may soon be marching off to a desert conflict as a staff sergeant with the Utah National Guard.

President Bush is reviewing a Pentagon proposal to summon as many as 150,000 members of the National Guard and other military reserve units to support troops deployed in Saudi Arabia and the Persian Gulf. White House officials say it is virtually certain that the President will authorize at least a limited call-up.

While no timetable has been set for the first large-scale mobilization of the nation’s civilian militia in 20 years, U.S. officials say the first wave of call-up notices could be issued early this week. The armed services have proposed activating up to 80,000 Army reservists and about 35,000 each from Navy and Air Force reserve units.

Metzger expects that he could be among the first to be called. “I have no desire to pull a trigger and I have no desire for our country to pull a trigger,” said the 29-year-old reservist, who is married with no children. “But that possibility exists, and our country has to be prepared for it. I am prepared.”

The value the Pentagon places on reservists like Metzger reflects the changing nature of America’s armed forces. And their performance during a large-scale mobilization in the Mideast crisis will provide the first real test of the Pentagon’s ability to field an effective fighting force that relies to a large extent on reserves.

Prevented by fiscal and political constraints from having active-duty forces with every specialty needed in a major military deployment, the nation has grown increasingly dependent on its reserves to fill in the gaps, say Pentagon officials and observers.

Since the end of the draft in 1973, the Pentagon has adopted a “Total Force Policy” that calls for shifting certain tasks--such as supply transport, medical services, communications and civil affairs--away from full-time warriors to part-time, civilian reservists.

For example, reserves now account for 97% of the Army’s civil affairs units and 61% of its hospital units, 97% of the Navy’s cargo-handling battalions, 62% of the Marine Corps’ bulk fuel units and 67% of the Air Force’s medical evacuation crews.

Short of a declaration of war, the President has the ability to mobilize up to 200,000 of the nation’s 1.7 million reserves for up to 90 days. Once the call-up decision has been made, Pentagon officials determine which reserve units will be needed and what supporting roles they will play in the military operation, officials said.

In the current standoff with Iraqi President Saddam Hussein, a decision to call up the reserves “would be killing three birds with one political stone,” said Martin Binkin, a senior fellow and defense specialist at the Brookings Institution in Washington.

Binkin said it would send a signal to Hussein of America’s resolve, a signal to the reserve forces that they are key players in the national defense and a signal to the American people that the Middle East crisis should be taken seriously.

“It’s a political decision,” Binkin said. “It’s an unambiguous signal that the nation is ratcheting up its defenses to an international concern.”

Laird Anderson, who retired last year as a U.S. Army Reserve colonel, said a presidential decision to call up large numbers of reserves would entail potential domestic pitfalls because mobilization of civilians would create “political, social and economic . . . dislocations.”

By deploying large numbers of reserves, he said, the President “would be putting this country on a war footing.”

And that, in turn, would require the reservists to abandon their peacetime occupations and lifestyles to become part of the American military machine. Although most are unlikely to be sent into combat, they probably would be relocated to military duty posts across the country.

“They’re going to be yanked from their homes and jobs,” Anderson said. “They’re going to be reporting somewhere, and they’re going to be sent somewhere else to work. All this takes time, but it can be done rather quickly after the President decides it must happen.”

Pentagon officials are pressing Bush to call out the reserves for more practical reasons. They note that the armed forces cannot sustain the current Middle East buildup--now approaching 50,000 troops and growing rapidly--without a heavy infusion of reserves to perform a variety of support, logistic and tactical jobs in the United States and abroad.

The reserve units and individuals likely to be included in an initial call-up would be selected because they have special skills or abilities not easily found among the active-duty fighting forces being deployed to the Middle East.

Metzger, for example, is more likely to be summoned for a noncombat role as a linguist rather than a front-line fighter. Formerly stationed in Germany on active duty with the U.S. Army, he speaks fluent German.

The Utah National Guard, where Metzger trains one weekend a month and two weeks during the summer, is noted for its heavy concentration of reservists with an ability to speak various foreign languages.

While they drill and march and shoot like regular soldiers, they also practice keeping their language skills sharp because the Pentagon is more likely to call on their unit to communicate with foreigners than to kill the enemy.

“Most of the people in this brigade have a language ability,” Metzger said. “That is the main reason the federal government would want us.”

Anderson, the retired Army reservist, said many specialized functions are performed by reservists because the military budget is needed to maintain full-time fighting forces.

“The regular Army can’t do everything,” he said. “It’s not affordable. There are many specialties that would have to come from the reserves. They’re cheap soldiers.”

In fact, Anderson said, some reservists already are being used in Operation Desert Shield--the military code name for the Middle East operation--as pilots transporting troops and supplies to Saudi Arabia and in other capacities not disclosed by the Pentagon.

“I’ve heard reports about some of these things that reservists are doing: flying refueling flights, transporting troops and so on,” he said. “It seems to me that the reserves are an essential part of this buildup already.”

Times staff writer Melissa Healy contributed to this story.