U.S. Ships, Planes Quickly Deployed to Troubled Area : Military: But experts warn that the Pentagon’s options are limited unless the Saudis invite Americans.

The Pentagon stepped up air patrols in the Persian Gulf and began moving warships, equipment and supplies into the area in a signal to Iraq that the United States would act to halt further aggression, Administration sources said Thursday.

Only hours after Iraqi troops overran Kuwait, ships loaded with military hardware, ammunition, food, fuel and other supplies set sail from the U.S. military base at Diego Garcia in the Indian Ocean.

At the same time, regional military experts in and out of the Pentagon warned that unless Saudi Arabia invites U.S. forces to use its elaborate network of bases, U.S. military options are limited.

“We’re moving stuff, and we’re positioning a carrier and other battle groups in and near the Persian Gulf to send a message: Saddam, beware,” said a military officer involved in the operation, referring to Iraqi President Saddam Hussein. “But we will not move troops around unless the Saudi northern provinces are threatened.”

Retired Adm. William J. Crowe Jr., immediate past chairman of the Joint Chiefs of Staff, agreed: “The United States can’t do anything militarily unless the Saudis cooperate. If the Saudis don’t invite us in, our options militarily are very limited. And the Saudis probably won’t invite us,” for military and diplomatic reasons.

A U.S. aircraft carrier battle group steamed toward the region Thursday while other ships were diverted from regular deployments to beef up U.S. naval forces, according to sources. American fighter planes and radar surveillance craft increased air activity in the northern gulf in an additional signal of U.S. resolve to try to halt further military moves by Hussein.

The United States maintains a large store of equipment at Diego Garcia to support military operations in the Middle East and Persian Gulf. The gear, packed aboard ships and on docks ready for loading, will support a 16,500-man Marine Expeditionary Brigade for 30 days of full-fledged combat.

With Iraq’s apparent military defeat of Kuwait in what one Pentagon official called a “one-day war,” defense officials weighed a number of potential additional military responses designed to discourage Hussein’s forces from crossing into Saudi Arabia, while diplomats try to nudge Iraqi troops out of Kuwait.

Bush said Thursday that, although diplomatic efforts will continue, U.S. action in response to the Iraqi invasion of Kuwait is possible.

“We’re not ruling any options in, but we’re not ruling any options out,” he declared.

But Crowe and other experts said that effective intervention could prove difficult.

The Navy, even with its carrier-based aircraft and its highly accurate long-range cruise missiles, would not be able to make much of a difference, except in a full-scale war between Iraq and Saudi Arabia, Crowe said.

“There’s not much the U.S. Navy can do. We’d have to get land-based air power into Saudi Arabia” to tip the balance of power in the Saudis favor, Crowe added.

Iraq has an estimated 1 million men under arms, while Saudi forces number 65,000, according to the authoritative International Institute for Strategic Studies in London. The Iraqi air and land forces are not only far larger but better equipped and more experienced than those of Saudi Arabia or any other Arab nation.

“We’ve got to draw the line at Saudi Arabia in terms of our interest and the free flow of oil,” Middle East military analyst Martin Indyk said. “But whether we can defend that line depends on the Saudis. They have to be prepared to stand up to (Hussein)--and I’m not sure they’re up to that.

“We can’t get ahead of the Arabs on this. If they’re not prepared to defend themselves, we’re not in a position to do it,” added Indyk, of the Washington Institute for Near East Policy.

Pentagon sources said that if invited by Saudi Arabia, several squadrons of U.S. warplanes could touch down at Saudi air bases within a day or two.

“If they’re prepared to give us access, we can get a lot of air power and send a strong message to Hussein” that he must not step over the new line in the Saudi sand, Indyk said.

The Saudi bases were designed by the U.S. military and built to American standards during more than a decade of intensive Saudi Arabian military purchases. They could serve easily as operating bases for U.S. warplanes.

Officials said that while naval forces can operate more freely to demonstrate American resolve, their usefulness in the Persian Gulf also is limited.

While eight warships plied the Persian Gulf on Thursday, the largest and most potent of the Navy’s weapons, the aircraft carrier, is too big to operate inside the constrained waters of the gulf. Once it arrives just outside the gulf, the aircraft carrier Independence will be far from Kuwait and from northern Saudi Arabia.

The distance makes air operations difficult and, moreover, such operations would be vulnerable to Iraq’s large and well-trained air force. Without Saudi land bases, they would be of limited use in punishing Hussein’s ground forces or in deterring their incursion into Saudi Arabia.

Officials said American warships could help to blockade Iraq’s effort to move Kuwaiti oil through the Persian Gulf and onto the world market. But because Iraq moves the majority of its oil onto the market through Turkey and Saudi Arabia, a blockade of Kuwaiti oil would be only partly effective. Unless Saudi Arabia and Turkey participate by cutting off the flow of Iraqi oil through pipelines on their soil, the Navy cannot inflict economic pain on Iraq.

By late Thursday, officials said Saudi Arabia had not made a formal request for American military assistance, although Sheik Saud al Nasir al Sabah, Kuwait’s ambassador to Washington, made an impassioned plea to “all our friends around the world” for military aid against the Iraqis.

Middle East experts said that while it is acutely aware of its inability to cope with Iraq by itself, Saudi Arabia would likely resist any entreaties to let U.S. forces in.

“The Saudi policy seems to be to stick their head into the jaws of the lion until they’re absolutely sure he’s going to close it,” Indyk said.

Staff writer Robin Wright contributed to this report.

MILITARY PRESENCE IN THE PERSIAN GULF Iraq: Troops: 1 million, army has 42 infantry divisions with 20 special forces brigades Tanks: 5,500 Aircraft: Up to 3,500 pieces Artillery: About 500 combat warplanes Naval ships: 51 Kuwait: Troops: 20,300, maintains small but well-equipped army with two armored brigades, a mechanized infantry brigade, an artillery brigade and a surface-to-surface missile battalion Tanks: 275 Aircraft: 36 combat aircraft Naval ships: 46 Saudi Arabia: Troops: 65,700 Tanks: 550 Aircraft: 180 warplanes and nine missiles. Artillery: 450 missile launchers and artillery pieces Iran: Troops: 600,000 Tanks: 500 Aircraft: 190 warplanes, 110 battle helicopters and 50 Scud missiles Naval ships: Three destroyers and five frigates Artillery: 900 artillery pieces and rocket launchers United Arab Emirates: Troops: 43,000 Tanks: 207 Aircraft: 60 warplanes and 19 armed helicopters Artillery: 115 artillery pieces and multiple rocket launchers Oman: Troops: 25,500 Tanks: 75 Aircraft: 62 combat aircraft Artillery: 75 artillery pieces and rocket launchers Qatar: Troops: 7,000 Tanks: 24 Aircraft: 13 combat, 16 armed helicopters Artillery: 14 pieces Bahrain: Troops: 3,350 Tanks: 54 Aircraft: 13 combat, 16 armed helicopters Artillery: 20 pieces U.S. AIRCRAFT CARRIER INDEPENDENCE Sailing from the Indian Ocean, a battle group including the Independence is headed for the Persian Gulf. The Independence is a conventional powered carrier which carries over 5,000 sailors and airmen. Among the approximately 80 Navy warplanes are: 20 F-14 fighters 20 F-18 attack jets 20 A-6 bombers A variety of radar warning support aircraft Also included in the six-ship battle group are: Two cruisers One destroyer Two frigates One ammunition ship Source: Times Wire Services/Los Angeles Times