The United States has sharply increased military movements toward the Middle East over the past three days, deploying additional naval forces, Marines and combat power amid escalating tensions with Iran, according to U.S. officials and public reports.
The USS Theodore Roosevelt carrier strike group departed San Diego on Sept. 27, while the Makin Island Amphibious Ready Group followed on Sept. 28 with more than 2,000 Marines. The deployments could add roughly 9,000 to 10,000 U.S. sailors and Marines to the region.
If current plans proceed, three U.S. aircraft carrier strike groups could be operating in or around the Middle East by late October. The USS George Washington and USS George H.W. Bush are already operating in the region, while additional destroyers and amphibious forces are deployed across surrounding waters.
The buildup comes as tensions between Washington and Tehran remain high, with diplomatic efforts continuing alongside preparations that would give the U.S. additional military options in the region.
Carrier and Amphibious Deployments
The Nimitz-class nuclear-powered aircraft carrier USS Theodore Roosevelt departed San Diego Naval Base on Sept. 27. According to USNI News, the ship turned on its AIS transponder at 9:10 a.m. that day and left San Diego Bay with tug assistance less than 20 minutes later. It then sailed west at more than 24 knots before shutting off its AIS signal about three hours later, entering radio silence.
The Roosevelt is the flagship of Carrier Strike Group 9, nicknamed the “Big Stick.” Its escort ships include three Arleigh Burke-class guided-missile destroyers — USS Paul Hamilton, USS Decatur and USS Carl M. Levin — as well as the Ticonderoga-class guided-missile cruiser USS Chosin. The Chosin will serve as the integrated air and missile defense commander for the strike group, a role that becomes critical when entering an active theater.
The Makin Island Amphibious Ready Group departed San Diego on Sept. 28, led by the amphibious assault ship USS Makin Island. The group also includes the amphibious transport dock USS John P. Murtha and the dock landing ship USS Anchorage. It is carrying more than 2,000 Marines from the 13th Marine Expeditionary Unit.
Combined, the transiting fleet carries more than 7,000 sailors and about 2,000 Marines. With forces already in theater, U.S. naval and Marine personnel in the Middle East will exceed 20,000 after reinforcements arrive. The Pentagon has also sent nearly 10,000 additional soldiers, pushing the total number of U.S. troops in the region above 50,000.
Two other carrier strike groups — the USS George H.W. Bush and the USS George Washington — are already operating in the region. The Boxer Amphibious Ready Group, with the 11th Marine Expeditionary Unit and about 4,200 Marines, arrived in April. The Washington was sent to the Middle East to replace the USS Abraham Lincoln, which drew attention after reports of mental health crises, including a suicide attempt, among its crew. The Wall Street Journal reported that the Washington may return to its home port in Yokosuka, Japan, after the Roosevelt arrives, which would bring the carrier total back to two.
Diplomacy Stalls as Military Pressure Mounts
The large-scale deployment comes amid stalled U.S.-Iran diplomacy. During talks in Pakistan in April, Washington proposed a 20-year suspension of Iranian nuclear activity, while Tehran counteroffered a five-year pause. The United States insists that Iran dismantle its nuclear facilities at Fordow, Natanz and Isfahan. Iran has said its missile deterrent capability and regional influence are non-negotiable “red lines.”
President Donald Trump told Time magazine that it was “possible” he would order heavier strikes on Iran after the Nov. 3 midterm elections. He also said he rejected an Iranian proposal to reopen the Strait of Hormuz, calling it “not good enough.”
The U.S. has also sent two Patriot air defense systems to Saudi Arabia and Qatar to protect oil and gas production facilities. The Treasury Department has imposed new sanctions on Iran’s railway and automotive sectors and their foreign suppliers.
Casualties and Maritime Tensions
The U.S.-Iran conflict, which began in late February, has killed 19 U.S. service members and wounded 861, according to official figures. On Sept. 14, an Iranian anti-ship cruise missile hit a transiting vessel in the Strait of Hormuz, injuring eight Marines. The injured suffered smoke inhalation and possible traumatic brain injuries. The Pentagon initially did not disclose the casualties; the information was added to an online casualty database several days later.
U.S. Central Command said its forces have diverted 115 merchant ships as part of a maritime blockade and have helped more than 1 billion barrels of oil pass through the Strait of Hormuz in recent months.
Iran Prepares Broader Retaliation
Iran is preparing a wider and more powerful set of retaliation options, according to three senior Iranian officials who spoke to Reuters. Senior commanders are studying targets beyond U.S.-linked interests, including countries that support U.S. operations, and potentially targets outside the Middle East. Iran has asked its allies in Lebanon, Yemen and Iraq to prepare to support Tehran if the U.S. resumes large-scale strikes.
In Yemen, Houthi forces recently captured the Red Sea port of Mocha, creating a new threat to shipping. Saudi Arabia views the Red Sea as an alternative route to the Persian Gulf, but the U.S. Navy and Saudi Navy have not yet been able to form an effective escort convoy to protect tankers. Houthi forces previously fired two anti-ship ballistic missiles at the U.S.-linked vessel Sea Champion.
Gulf states are also adjusting their positions. Saudi Arabia has agreed to allow U.S. forces to use King Fahd Air Base in the west of the country. The United Arab Emirates has closed a Dubai-based Iranian hospital and an Iranian club, and has restricted Iranian assets. Saudi Foreign Minister Faisal bin Farhan warned that “any belief that Gulf states are incapable of responding is a miscalculation.”
White House Security Meeting
On Oct. 3, Vice President JD Vance hosted an unannounced senior security meeting at Camp David. Attendees included Secretary of State Marco Rubio, Defense Secretary Pete Hegseth, Middle East envoy Steve Witkoff, CIA Director John Ratcliffe and Gen. Dan Caine, chairman of the Joint Chiefs of Staff. The meeting lasted several hours and discussed Iran and the Houthi conflict in Yemen.
Trump convened a similar Camp David meeting in June 2025. Days later, Israel launched military action against Iran. The overlap in attendees has fueled speculation that Washington may be nearing a major military decision.
Analysts Warn of Rising Risk
Analysts say the U.S. buildup gives Washington more military options and additional leverage in diplomatic talks. Niu Xinchun, director of the China-Arab States Research Institute at Ningxia University, said Trump’s preferred outcome is to use military threats to force Iran back to the negotiating table and reach a deal before the midterm elections.
But with core differences still sharp, the risk of another large-scale U.S.-Iran conflict is rising.
This report is based on the information provided and public accounts; some operational details could not be independently verified.
