ABOARD THE USS ENTERPRISE — The machine guns are tested once a week, warplanes armed with missiles are sent soaring over the Gulf nearly every day and more than half of the U.S. Navy’s minesweeping vessels are positioned nearby.

A surge of U.S. war power in the Persian Gulf has coincided with increased tensions over Iran’s nuclear ambitions and its threats to close the Strait of Hormuz. U.S. military commanders in the region say there is nothing unusual about the deployment of two — and soon three — carrier strike groups and more than half of the U.S. Navy’s minesweepers.

“We are not here for Iran,” said Rear Adm. Walter Carter, commander of the USS Enterprise strike group, in an interview aboard the aircraft carrier earlier this month. “I have seen nothing that matches the rhetoric that you hear sometimes.”

His comments to reporters aboard the Enterprise came less than two weeks before the start of the largest-ever multinational minesweeping exercise in the Persian Gulf. More than 20 countries are scheduled to take part in the exercise, being held from Sept. 16 through Thursday, according to the Pentagon.

The unprecedented display of strength suggests the United States is locked in a delicate dance requiring the suggestion of force while not directly antagonizing Iran, said Yoel Guzansky, a research fellow at the Institute for National Security Studies in Tel Aviv and a former member of Israel’s National Security Council.

“Every day or so, we are hearing about another ship headed for the Gulf,” Guzansky said. “The U.S. is doing a lot of effort to show that it is doing a buildup in the Gulf.”

In Senate testimony in June, former Sen. Charles Robb, co-chair of the Bipartisan Policy Center’s Task Force on Iran, used stronger terms.

“High-ranking defense officials, including the secretary of defense, should ... oversee military exercises designed to counter Iranian threats to the region,” he said. “In essence, this is a form of strategic communication designed to reassure our security partners and signal the seriousness of our intentions to Tehran.”

Iran has long had a fractious relationship with the United States and other nations, but the threatening rhetoric from all sides has grown louder in recent months.

A report from the U.N.’s International Atomic Energy Agency last month concluded that since May, Iran has more than doubled the number of uranium-enrichment centrifuges at a subterranean site south of Tehran, heightening concerns that it is seeking develop nuclear weapons. Iran maintains it is pursuing peaceful nuclear technologies.

Israeli leaders have urged the United States to take stronger action against Iran to prevent it from becoming a nuclear power and threatening the region, and warned that Israel could release the first strike, potentially triggering a multinational conflict.

The United States has emphasized diplomacy while building up its capabilities in the region.

The Navy doubled the number of minesweepers in the region earlier this summer to eight vessels, or more than half of its fleet of 14 ships. In July, the Navy announced it would deploy the aircraft carrier USS John C. Stennis and its strike group four months early, sending it to the Middle East rather than the Pacific as planned. The Stennis left Washington state on Aug. 27. The Navy also sent the Ponce, its first floating forward base, to the Persian Gulf in July.

The Enterprise, the Navy’s first nuclear-powered aircraft carrier, deployed to the region earlier this year, joining the USS Eisenhower. From 2003 to early 2007, there was only one carrier deployed in the region, according to a Navy spokesman.

Carter said the Enterprise, the Navy’s largest and oldest aircraft carrier, has traveled through the Strait of Hormuz without issue more than eight times since it arrived. During those trips, Iranian military officials often took pictures of the vessel and asked how many people were on board — standard maritime security procedures, Carter said.

“They have been professional and courteous mariners,” Carter said. “Right now, I don’t view them as a threat to us.”

The Enterprise was positioned during the reporters’ visit about a day’s travel away from the Strait, just north of mainland Oman.

Aircraft were sent nearly every day over Pakistan and into Afghanistan to provide air support to ground operations there. The fighter jets spend three hours in the air over Afghanistan communicating with NATO and U.S. military officials on the ground before refueling and flying back.

Cmdr. Jason Velivlis, who oversees one of the Enterprise’s eight aircraft squadrons, said he hadn’t released any bombs while flying over Afghanistan this year. He’s not sure if a conflict with Iran would demand more firepower. His bosses hadn’t discussed the possibility with him.

“We typically don’t feel much of that tension on a day-to-day basis,” he said. “We are aware of it from watching the news.”

Capt. William Hamilton, the Enterprise’s commanding officer, said the ship’s actions are often interpreted to be aggressive, even during routine operations.

In June, the Enterprise traveled in international waters roughly 70 miles south of Pakistan, prompting speculation that the ship was sending a warning to the nation after it blocked key NATO supply routes to Afghanistan.

“It was just an overreaction,” Hamilton said. “We didn’t get that close.”

The USNS Rappahannock’s recent attack on a small Indian fishing vessel near the United Arab Emirates illustrates how tensions have deepened across the region, Guzanksy said. The July incident occurred after U.S. sailors fired rounds from a .50-caliber machine gun toward the approaching vessel after it ignored orders to turn away.

“Any small mistake can be escalated into a conflict now,” Guzanksy said. “It is very tense now. The Gulf is very, very hot. All sides are nearing the finish line and (war) seems closer than ever.”

silvac@stripes.osd.mil Twitter: @cristymsilva

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