Tracking the US military build-up today in the Middle East

Editor's note: Last updated on Jan. 29, 2024, at 10:35 a.m.

The U.S. has significantly increased its military presence in the Middle East in the nearly three weeks after Hamas launched attacks against Israel and took hundreds of hostages on Oct. 7. Among other things, the Pentagon has deployed two aircraft carrier strike groups as well as a range of fighter aircraft to the region.

The official reason for the new deployments is to deter Hamas’s allies, including Iran and Hezbollah, from launching attacks against Israel and sparking a wider regional war. That logic will be put to the test in the coming days if Israel follows through on its planned ground invasion of Gaza, which is sure to face sharp condemnation from throughout the Middle East.

Meanwhile, the Pentagon has accused Iranian-backed militias of carrying out a series of attacks against the roughly 3,400 U.S. forces that remain in Syria and Iraq; 24 U.S. personnel have been injured so far. In total, reports say there are currently about 35,000 U.S. troops throughout the region, though most are stationed at bases in the Gulf, far away from the fighting.

Below is a full timeline of new, publicly reported deployments of U.S. troops and military assets to the region since October 7. RS will continue to update this tracker as the crisis continues.

Jan. 28

An Iraqi militia hit a U.S. outpost in Jordan near the Syrian border, killing three U.S. soldiers and injuring 25. The attack is the first to kill American service members in the Middle East since Oct. 7. Jordanian authorities deny that the attack hit within their territory.

Jan. 24

The U.S. military was attempting to escort U.S.-flagged container ships through the Red Sea when the flotilla came under fire from Houthi missiles, forcing the cargo ship to turn back. American officials said none of the ships were hit in the attack. The container ships are carrying cargo belonging to the Pentagon and Department of State, among other U.S. agencies.

DoD told Politico that its expanded operations in the Middle East since Oct. 7 will cost $1.6 billion, not including the cost of missiles fired at Houthi targets in Yemen. The Pentagon contends that it will not have enough money to pay for this until Congress passes additional funding, though some experts dispute this claim, arguing instead that the military "has considerable flexibility within its $800 billion-plus budget to deal with short-term contingencies."

Jan. 23

The U.S. conducted strikes against Iraqi militias in response to an ongoing string of attacks on U.S. forces in Iraq, including one that injured four American soldiers and one Iraqi official. The precise impact of the U.S. strikes remains unclear.

Jan. 22

Following days of U.S. and UK airstrikes against Houthi facilities, the Pentagon gave an official name to the actions: Operation Poseideon Archer. As CNN notes, this designation "suggests a more organized, formal and potentially long-term approach to the operations in Yemen." The Western militaries have now carried out at least eight rounds of airstrikes in the past 10 days, according to Politico.

Jan. 16

The U.S. attacked more Houthi sites in Yemen, including strikes on facilities related to anti-ship missiles, according to Reuters.

CENTCOM announced that it seized Iranian weapons headed for the Houthis on Jan. 11. Two Navy SEALs fell into the sea near Somalia during the operation, and a large search and rescue effort is now underway to find them. If the SEALs did not survive the operation, it would mark the first deaths among U.S. forces related to spillover from the Gaza war.

Meanwhile, the Pentagon is in the process of deploying 1,500 New Jersey National Guard troops to Iraq and Syria, where they will replace soldiers from the 10th Mountain Division as part of the campaign against ISIS. In a statement to RS, DoD described the move as a "planned replacement of forces" and said the U.S. does not plan to increase troop levels to more than about 2,500 soldiers in Iraq and 900 soldiers in Syria.

Jan. 15

The Houthis hit a U.S.-owned cargo ship in the Red Sea in an attack that caused limited damage. The move "will add to fears that the US and UK strikes on Houthi targets in Yemen have not degraded the militia group’s ability to threaten commercial shipping," the Guardian notes. The Houthis continue to argue that the attacks will stop if a cease-fire is reached in the Gaza war.

Jan. 14

The Houthis fired a cruise missile at the USS Laboon, which American forces shot down using a fighter jet.

Jan. 12

The U.S. launched a second attack on Houthi targets in Yemen, hitting at least one radar station, according to CNN. The missiles were launched from the USS Carney.

Jan. 11

The U.S. and United Kingdom launched a large-scale attack on Houthi assets in Yemen in a major escalation of Washington's hostilities with the armed group. The Houthis say they are attempting to blockade of Israel by attacking Israeli ships in the Red Sea, though the attacks have led to a large overall drop in shipping traffic through the Suez Canal. The Biden administration said it hoped the attacks would deter future attacks.

Jan. 10

The U.S. and UK thwarted a drone and missile attack launched from Houthi-held territory on Tuesday. No damage resulted from the attack. Despite Western efforts to secure the Red Sea, many major shipping companies continue to avoid the key waterway, which is the entrance to the Suez Canal from the east.

Jan. 9

The U.S. conducted an air strike Tuesday that stopped an attack on the Ain al-Asad military base in Iraq, according to Reuters. The bombing could further inflame tensions in the country given the harsh reactions of Iraqi officials to previous strikes.

Jan. 4

A prominent Iraqi militia commander died in a Thursday airstrike in Baghdad that the Popular Mobilization Forces blamed on the United States without providing evidence. The attack, while also killed two others, may be a U.S. response to months of attacks from the PMF and its affiliated groups, which have close ties to Iran. A Pentagon official confirmed to the New York Times that the U.S. was indeed behind the attack, which comes just a day after many in Iraq and Iran marked the fourth anniversary of the U.S. killing of an Iranian general and a top PMF commander.

Jan. 1

The USS Gerald Ford aircraft carrier strike group is returning home following a lengthy patrol mission in the eastern Mediterranean and Red Sea, according to Politico. The ship will be spelled by the USS Bataan and a pair of other ships. The U.S. now only has one aircraft carrier group — led by the USS Dwight Eisenhower — patrolling in the region.

Meanwhile, Iran sent a destroyer into the Red Sea on Monday, though it remains unclear what mission the ship is carrying out.

Dec. 31

The U.S. sunk three of four Houthi boats that were attacking a commercial ship in the Red Sea in the most deadly U.S.-Houthi fighting since the Gaza conflict began. The helicopters that destroyed the boats came from the USS Eisenhower carrier strike group, which has patrolled in the eastern Mediterranean and now Red Sea region since October.

A series of Dec. 30 airstrikes in Syria that were previously attributed to the U.S. are now believed to have been carried out by Israeli forces, according to Voice of America. The attack killed 23 fighters from groups supported by Iran, including Hezbollah.

Dec. 28

The USS Mason downed a Houthi missile and drone in the Red Sea on Thursday. The Houthi attack, which led to no injuries or damage, was the 22nd such strike since October.

Dec. 26

The U.S. shot down more than a dozen Houthi drones and missiles in the Red Sea on Tuesday, according to the Jerusalem Post. Meanwhile, the Indian military announced that it sent some of its destroyers to patrol, most likely in the Persian Gulf and Red Sea area.

Dec. 19

Defense Secretary Lloyd Austin announced "Operation Prosperity Guardian" — a multinational military task force that will address Houthi attacks in the Red Sea — during a visit to Bahrain. Despite initial reports that a number of Arab countries would help with the initiative, Bahrain was the only Middle Eastern state to join, signaling an unwillingness among regional leaders to openly oppose the Houthi attacks. Participants in the task force include Canada, France, Italy, the Netherlands, Norway, the Seychelles, Spain, and the United Kingdom.

The U.S. has also sent several destroyers through the Bab al-Mandeb Strait in an effort to deter attacks.

Dec. 18

Secretary of Defense Lloyd Austin visited Israel on Monday during a trip in which he is expected to announce a new maritime protection task force to counter the Houthis' efforts to stop shipping in the Red Sea. Houthi attacks have forced five major shipping companies to redirect their ships away from the Red Sea altogether, forcing them to sail around the Cape of Good Hope instead of through the Suez Canal. It is not clear whether the task force will require the U.S. to send additional troops to the region, but it will reportedly involve Bahrain, Egypt, Jordan, Oman, Qatar, Saudi Arabia, and the United Arab Emirates.

Dec. 16

The U.S. is "actively weighing options to strike back at Houthis in Yemen" following an uptick in attacks on civilian and military ships in the Red Sea, according to Politico. The Pentagon has moved the Eisenhower aircraft carrier strike group to the Gulf of Aden "to support a potential U.S. response to attacks," the article notes.

Dec. 8

A rocket barrage hit the U.S. Embassy in Baghdad on Friday, according to AP News, which said the attack caused some damage but did not lead to casualties. Officials said militants launched 14 Katyusha rockets at the compound, some of which fell near the embassy's gate while others splashed into the nearby Tigris River. There have now been 78 attacks on American facilities in Iraq and Syria since October.

Dec. 3

A U.S. warship shot down three drones in the Red Sea amid a barrage that hit three commercial ships in the area, according to AP News. The Houthis, a Yemen-based militant group, claimed responsibility for two of the attacks. CENTCOM says the U.S. will "consider all appropriate responses" to the strikes, which it described as "a direct threat to international commerce and maritime security." U.S. officials also argued that "these attacks, while launched by the Houthis in Yemen, are fully enabled by Iran," which has long maintained close ties with the Houthis.

The U.S. also carried out an air strike in Iraq, killing five Iraqi militia members, according to Reuters. An American official said the attack hit a drone staging site near Kirkuk that was being used for strikes on U.S. soldiers in the country.

Nov. 26

The Houthis fired two ballistic missiles in the direction of an American destroyer in the Gulf of Aden, though a Pentagon spokesperson later played down the news and argued that it is "not clear to us who they were targeting exactly." The missiles, which missed their purported target by about 10 nautical miles, were apparently a response to the Navy's arrest of Somali pirates who had attempted to seize an Israeli-owned tanker.

Nov. 21

The Pentagon said U.S. forces bombed Iran-backed militants who had fired a ballistic missile at the Al Asad Air Base in Iraq, injuring eight people and causing minor damage to infrastructure. The U.S. retaliatory attack killed three of the militants, marking the second lethal response to such attacks by U.S. troops, who have now killed at least 9 fighters belonging to Iran-affiliated militias over the past month. American soldiers have come under fire in Iraq and Syria 66 times since October, according to the Defense Department.

Nov. 20

Amos Hochstein, a senior adviser to President Joe Biden, landed in Israel today "for talks with senior Israeli officials on preventing a war between Israel and Lebanon," according to Axios. Hochstein is reportedly hoping to persuade Israel to tone down its strikes against Hezbollah, which some U.S. officials worry is an attempt to "create a pretext for a wider war in Lebanon that could draw the U.S. and other countries further into the conflict."

Nov. 19

Defense Department officials are growing increasingly frustrated with "what they consider an incoherent strategy for countering the Iranian proxies" who have continuously attacked U.S. troops in Iraq and Syria over the past month, according to the Washington Post. The Post's reporting suggests that some officials want the Biden administration to strike back more aggressively against these groups, while the White House says that its more careful approach has helped prevent further escalation in the Middle East.

Nov. 15

A U.S. Navy destroyer shot down a drone in the Red Sea that was "heading in the direction of the ship," according to a Pentagon official who spoke with Al-Monitor. The projectile was originally fired from Yemen, likely by the Houthis, who are aligned with Iran and have fired missiles at Israel in recent weeks.

Nov. 12

U.S. Central Command announced Sunday that it had carried out airstrikes against two IRGC targets in eastern Syria, more specifically, "facilities near the cities of Abu Kamal and Mayadin." The New York Times reported that Air Force F-15E fighter jets struck several buildings in Abu Kamal "used for training and storing munitions," and "a safe house in Mayadin used as a command headquarters."

On Saturday, the Pentagon said U.S. troops have come under 48 attacks in Iraq and Syria since Oct. 7, leaving 56 U.S. personnel injured.

Nov. 8:

The Pentagon announced that it carried out an airstrike against a weapons store in eastern Syria that the U.S. says belongs to Iran's Revolutionary Guard Corps and its partners in the region. The bombing, which was conducted by two F-15s, was done in response to recent attacks on U.S. facilities in Iraq and Syria by Iranian-backed groups.

An American MQ-9 Reaper drone was shot down off the coast of Yemen, and U.S. officials are "assessing the incident," according to a Pentagon official who spoke with the BBC.

Nov. 6:

Since October 17, 38 attacks on U.S. forces in Iraq and Syria have injured 45 U.S. soldiers, the Department of Defense revealed today. Most of those injuries, which are reportedly minor, came from a pair of attacks on the al-Tanf base in Syria on October 18.

Nov. 5:

CENTCOM announced that an Ohio-class submarine entered into its area of responsibility but did not share details about the vessel's exact location.

Nov. 3:

The Islamic Resistance in Iraq — an apparent cover group for Iran-linked militias in the country that has emerged since Hamas's attack — claimed to have hit an American base in Erbil. The Pentagon has yet to comment on the alleged strike.

Nov. 2:

The Pentagon is actively flying surveillance drones over the southern Gaza Strip in an attempt to help with hostage recovery efforts, according to the New York Times. Officials told the Times that these drones have been doing surveillance missions in the area for much of the past month, suggesting a deeper level of direct U.S. involvement in the conflict than has previously been revealed. The sources denied that the drones are providing any assistance to Israeli ground operations.

Oct. 31:

American special operations commandoes are working on the ground in Israel to help find hostages held by Hamas, according to an assistant secretary of defense. The soldiers are not directly participating in hostilities but are helping "advise" the Israel Defense forces on their operations in Gaza.

The Pentagon announced that it will send an additional 300 soldiers to the Middle East, specifying only that they are not going to Israel. A spokesperson for the Defense Department also said that U.S. forces have now faced 27 separate attacks in Iraq and Syria since October 17.

Earlier in the day, armed drones attacked America's Ain Al-Asad Airbase in Iraq, marking the 23rd strike on U.S. forces in Iraq and Syria since October 17. The attack did not result in any injuries.

Oct. 30:

Jordan requested that the U.S. send it additional Patriot missile batteries to bolster the country's border defenses amid ongoing tensions in the region, according to a spokesperson for the Jordanian military. The comment appears to confirm previous reports that the Pentagon has dispatched troops and missile defense systems to support Amman, a potentially controversial decision given widespread pro-Palestine views in the country. A spokesperson for the Jordanian Armed Forces also denied that the Department of Defense was using Jordan's territory to transport weapons to Israel.

Oct. 27:

The Pentagon said it struck "two facilities in eastern Syria used by Iran’s Islamic Revolutionary Guard Corps (IRGC) and affiliated groups" following recent attacks by Iranian-backed militias in Iraq and Syria. The Defense Department insisted that the strikes "are separate and distinct from the ongoing conflict between Israel and Hamas, and do not constitute a shift in our approach to the Israel-Hamas conflict."

Oct. 26:

900 additional U.S. troops are headed to the Middle East under CENTCOM command, the Pentagon told Politico. These soldiers will operate the additional air defense equipment that the Defense Department has moved into the region in recent weeks. The report also noted that the U.S. is sending two more Iron Dome missile defense systems to Israel.

Politico reported that 19 of the service members injured by attacks in Iraq suffered traumatic brain injuries. The diagnosis can include a wide range of symptoms, including headaches, dizziness, and blurred vision. All injured soldiers have since returned to duty.

Oct. 24:

The Pentagon announced that the U.S. is sending an additional squadron of F-16 fighter jets to the Middle East to “further enhance the ability of U.S. forces to defend themselves.” The Department of Defense also noted that it has put a variety of units on “prepare-to-deploy orders” ahead of potential future movement of troops to the region.

“Our message to any country or group thinking about trying to take advantage of this situation to widen the conflict is: Don't,” warned Pentagon Press Secretary Pat Ryder.

On the same day, the military confirmed that 24 U.S. personnel had been injured in at least 13 attacks in Syria and Iraq since October 17.

Oct. 23:

The U.S. sent a Marine general and several other military officers to Israel in order to advise the Israeli Defense Forces (IDF) on their ongoing campaign of airstrikes in Gaza, according to Axios. The American officers are not expected to remain in Israel following the invasion of Gaza, the report continued.

Oct. 22:

The USS Dwight D. Eisenhower aircraft carrier strike group was redirected to CENTCOM's area of responsibility after initially being sent to the eastern Mediterranean Sea to join another American aircraft carrier in the region, according to the Pentagon. The statement did not say exactly where the carrier would be based, but CENTCOM covers the Persian Gulf, Red Sea, and other waters near the Arabian Peninsula.

Oct. 21:

Secretary of Defense Lloyd Austin announced that the Pentagon is sending an additional THAAD missile defense battery and several Patriot missile defense battalions to the Middle East. While Austin did not reveal the locations of these deployments, the Wall Street Journal reported subsequently that the THAAD battery is headed to Saudi Arabia, while the Patriot systems are being sent to Kuwait, Jordan, Iraq, Saudi Arabia, and the United Arab Emirates.

Oct. 19:

The USS Carney shot down three missiles launched by the Houthi militant group in Yemen. The missiles appeared to be headed toward Israel, though their exact targets remain unclear.

Oct. 18:

The Ain al-Asad air base in Iraq came under attack from drones that were most likely launched by Iran-backed militias. U.S. forces shot down some of the drones, while others hit their targets and caused minor injuries.

Oct. 17:

CENTCOM Gen. Michael Kurilla visited Israel and held a series of meetings with Israeli military officials. “I'm here to ensure that Israel has what it needs to defend itself, and am particularly focused on avoiding other parties expanding the conflict,” Kurilla said.

Meanwhile, CNN reported that the U.S. is sending an additional 2,000 Marines to a location off the coast of Israel in a further attempt to deter Hamas’s regional allies from joining the fight. The rapid response unit is on the USS Bataan, which had previously been in the Gulf of Oman.

“Taken together, the moves are aimed at forestalling a wider regional war,” CNN reported. “But they also risk deepening the US’ involvement in a conflict in which the Biden administration is trying to avoid direct military action.”

Oct. 14:

The Pentagon announced its decision to move a second aircraft carrier strike group into the eastern Mediterranean as “part of our effort to deter hostile actions against Israel or any efforts toward widening this war following Hamas's attack on Israel.”

The group, led by the USS Eisenhower, also includes a cruiser and two destroyers as well as numerous fighter aircraft.

The U.S. also said that it has moved additional F-15, F-16, and A-10 fighter aircraft to the region.

Oct. 13:

Defense Secretary Austin visited Israel, where he held a series of meetings with Israeli political and military leaders, including Prime Minister Benjamin Netanyahu.

“Hamas attacked at a time of global challenge, but the United States is the most powerful country in the world, and we remain fully able to project power and uphold our commitments and direct resources to multiple theaters,” Austin said in response to concerns that the U.S. military is stretched thin by the wars in Israel and Ukraine. He also noted that American security assistance is “already rapidly flowing into Israel.”

Oct. 10:

The USS Gerald R. Ford aircraft carrier strike group arrived in the eastern Mediterranean, where it will help with intelligence operations and planning for efforts to rescue hostages, according to Al Monitor. The strike group also includes five smaller warships and a number of fighter aircraft.

Oct. 8:

Austin announced that the United States will move the USS Gerald R. Ford aircraft carrier strike group to the eastern Mediterranean. He also promised that the Pentagon “will be rapidly providing the Israel Defense Forces with additional equipment and resources, including munitions.”

“The first security assistance will begin moving today and arriving in the coming days,” Austin added.

CENTCOM also said that it has “taken steps to augment U.S. Air Force F-15, F-16, and A-10 fighter aircraft squadrons” in the Middle East.

Oct. 7: