But there were no incidents on Tuesday as the Lincoln's battle group crossed through the narrow strait, which Iran has threatened to close in retaliation for tighter Western sanctions.
Several U.S. choppers flanked the carrier group throughout the voyage from the Gulf. Radar operators also picked up an Iranian drone and surveillance helicopter in Iran's airspace near the strait, which is jointly controlled by Iran and Oman.
The top U.S. Navy official in the Gulf said Sunday he takes Iran's military capabilities seriously but insists his forces are prepared to confront any Iranian aggression in the region.
Vice Adm. Mark Fox, commander of the 5th Fleet, told reporters at the naval force's Bahrain headquarters that the Navy has "built a wide range of potential options to give the president" and is "ready today" to confront any hostile action by Tehran.
He did not outline specifically how the Navy might answer an Iranian strike or an effort to shut the entrance to the Persian Gulf, though any response would likely involve the two U.S. aircraft carriers and other warships cruising the waters off Iran.
"We've developed very precise and lethal weapons that are very effective, and we're prepared," Fox said. "We're just ready for any contingency."
Faced with tightening Western sanctions, Iranian officials have stepped up threats to close the Strait of Hormuz if the country's oil exports are blocked. A fifth of the world's oil supply passes through the narrow waterway, which is only about 30 miles (50 kilometers) across at its narrowest point.
Iran and Oman share control of the waterway, but it is considered an international strait, meaning free transit passage is guaranteed under international law.
Iran's army chief, Gen. Ataollah Salehi, early last month warned an American warship not to return to the Gulf shortly after the aircraft carrier USS John C. Stennis and another vessel left. Another carrier, the USS Abraham Lincoln, entered the Gulf without incident on Jan. 22.
Fox acknowledged that Iran's military is "capable of striking a blow" against American forces in the Gulf, particularly using unconventional means such as small attack boats or mines laid along shipping lanes.
"We're not bulletproof. There are people that can take a swipe at us," Fox said.
But he added that he has reminded officers under his command that they "have a right and an obligation of self defense" if attacked.
The admiral's comments echo those of other Western officials, who say they will respond swiftly to any Iranian attempt to shut the Strait of Hormuz.
Gen. Martin Dempsey, chairman of the U.S. Joint Chiefs of Staff, told CBS' "Face the Nation" last month that Iranian forces could block shipping through the strait "for a period of time," but added, "We can defeat that."
"They are a long-term partner and a very important piece of our ability to do our mission," he said of the country.
Bahrain has been rocked by protests led by the country's majority Shiites against the country's Sunni monarchy that erupted in force a year ago. Street battles between security forces and protesters still flare up almost daily in the predominantly Shiite villages around the capital.
Fox's command encompasses the bulk of the Middle East, including the Red Sea, the Persian Gulf and a large swath of the Indian Ocean along the east African coast. There are about 25,000 sailors under his command.