By air and sea, the United States and Britain were building up their military presence Thursday in the Persian Gulf, as people of the region worried about a rush to retaliate and wondered just how broadly America plans to act.

The U.S. Defense Department on Wednesday ordered more combat aircraft — fighter jets and bombers — to beef up its formidable presence in the Gulf region.

Britain was building up substantial forces in the area as part of a long-planned joint exercise with Oman — its largest naval deployment since the 1982 Falklands War.

Around the Gulf, many said they worry the buildup means the United States has far more in mind than Usama bin Laden, its prime suspect in the Sept. 11 terror attacks on the World Trade Center and the Pentagon that killed thousands. Without knowing details, there are fears of a rush to judgment and a large-scale war.

"I think it's too much for Afghanistan, too many troops," said Yousef Abdullah, a 33-year-old Bahraini accountant. "It's easy to start a war, but where are you going to stop?"

Iraq, often considered another potential U.S. target, indicated Thursday it wouldn't interfere in any American-Afghani war, with a state-run newspaper editorial saying to take any actions would invite U.S. attack.

Iraq "should be only an observer to the events," Babil newspaper, owned by Saddam Hussein's eldest son, Odai, said in a front-page editorial. "The Americans are not ready to accept any unexpected disturbances in the oil-rich Gulf region, so they will watch and hit Iraq should it take any actions."

The United States has maintained a large force in the Gulf since leading the Gulf war coalition that ousted Iraq from Kuwait in 1991. Combat planes are stationed in Saudi Arabia, Bahrain and Kuwait and weapons storage and other installations are located elsewhere in the Gulf.

The U.S. Navy's 5th Fleet is based in Bahrain; two aircraft carriers with their complements of guided missile cruisers and destroyers are in the Gulf and Arabian Sea. A third is heading from the United States to the Mediterranean, but its final destination wasn't clear.

As of Sept. 10, the day before the attacks on the United States, American forces in the Gulf numbered 8,220 sailors and Marines with 14 ships — including one carrier on its regularly scheduled duty, the USS Enterprise — according to the U.S. Navy website. Destroyers, guided missile cruisers, mine hunters were among the other ships.

Since then, the U.S. military has been on high alert, releasing no official information.

Cmdr. Jeff Alderson, spokesman for the U.S. Navy's 5th Fleet based in Bahrain, refused to comment Thursday on forces in the region, the planes being deployed or the readiness of the U.S. troops.

Britain has an aircraft carrier in the Gulf as well as four frigates, two destroyers, a helicopter carrier, assault craft, four minehunters, an armored division and 50-plus aircraft. More British ships, including destroyers, a submarine and a carrier, were expected to pass through the Suez Canal en route to the Gulf region beginning early Friday.

In Kuwait, where the U.S. military keeps squadrons of bombers and fighters at two of the country's air bases to patrol the skies over Iraq, there is understanding of American desire to respond. But concerns remain, particularly if the battle against terror begins to look like a war on Islam.

"{It is still not clear what the operation will be like, and there is no evidence against anyone," said Abdul-Mohsen Jamal, a lawmaker and member of Parliament's foreign affairs committee. "However, I don't believe that Kuwait will accept the bombing of any Muslim country."

The legislator said was briefed Wednesday by Foreign Ministry officials, who said Washington has not yet asked Kuwait for "anything specific." Kuwait has offered the United States its full political backing.

Majed al-Jehani, who runs a rental car business in Riyadh, also isn't convinced the United States has pinned down who is responsible and said he fears many innocent people will be hurt by retaliatory strikes.

"If they do this, it will be just the same as the terrorists did," al-Jehani said.