The United States carried out two airstrikes against facilities used by Iran’s Islamic Revolutionary Guards Corps and its proxies in eastern Syria early Friday in retaliation for a flurry of recent rocket and drone attacks against American forces in Iraq and Syria.
The strikes were intended to send a strong signal to Iran to rein in the attacks the Biden administration has blamed on Tehran’s proxies in Syria and Iraq without escalating the conflict in the Middle East, U.S. officials said. The targets represent a significant escalation in striking facilities used by Iran’s own forces in the region, not just the militias in Iraq and Syria that it helps arm and train.
“These precision self-defense strikes are a response to a series of ongoing and mostly unsuccessful attacks against U.S. personnel in Iraq and Syria by Iranian-backed militia groups,” Defense Secretary Lloyd J. Austin III said in a statement.
“The United States does not seek conflict and has no intention nor desire to engage in further hostilities, but these Iranian-backed attacks against U.S. forces are unacceptable and must stop,” Mr. Austin said.
Since Hamas’s surprise attack against Israel on Oct. 7, President Biden and his aides have sought to contain the war between Israel and Hamas, and prevent it from spilling over into a regional conflict with Iran and its proxies in Lebanon, Syria and Iraq.
To that end, the U.S. has deployed two aircraft carriers to the eastern Mediterranean near Israel and dozens of additional warplanes to the Persian Gulf region to deter Iran and its proxies in Lebanon, Syria and Iraq from engaging in a regional war. The Pentagon has also rushed additional Patriot antimissile batteries and other air defenses to several Gulf nations to protect U.S. troops and bases in the region.
But with the near daily attacks against U.S. forces over the past 10 days — the number climbing to at least 16 after the Pentagon confirmed an unsuccessful strike at a base in Erbil, Iraq, on Thursday — pressure has been mounting on the United States to respond militarily.
“These narrowly tailored strikes in self-defense were intended solely to protect and defend U.S. personnel in Iraq and Syria,” Mr. Austin said. “They 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.”
“Iran wants to hide its hand and deny its role in these attacks against our forces,” Mr. Austin said. “We will not let them. If attacks by Iran’s proxies against U.S. forces continue, we will not hesitate to take further necessary measures to protect our people.”
Mr. Biden, asked on Wednesday about drone strikes against U.S. military personnel in Iraq and Syria in recent days, said that he had warned Iran “that if they continue to move against those troops, we will respond.”
The predawn U.S. retaliatory strikes on Friday came just hours after the Pentagon announced that 19 U.S. military members based in Iraq and Syria have suffered traumatic brain injuries after rocket and drone attacks from Iran-backed militants last week.
The Defense Department had previously said that 21 service members had suffered minor injuries but returned to duty after the attacks on Oct. 17 and 18 at Al Asad Air Base in western Iraq and al-Tanf garrison in southern Syria.
Since Oct. 17, Iran-backed militia have carried out at least 12 rocket or one-way attack drone strikes against U.S. troops in Iraq and at least four attacks in Syria, Brig. Gen. Patrick S. Ryder, the Pentagon spokesman, said on Thursday. There are 2,500 troops in Iraq and 900 in Syria, mainly helping local allies conduct counterterrorism missions against the Islamic State.
“I believe there is concern that our bases in Syria and Iraq, especially Syria, could be attacked by a wave of drones and it could overwhelm the defenses currently there,” Mick Mulroy, a former defense official and retired C.I.A. officer, said this week.
General Ryder said on Thursday that 15 of the 17 service members injured at al-Tanf and all four of the troops hurt at Al Asad had subsequently been diagnosed with traumatic brain injuries.
“As we’ve seen in the past, there are situations where several days after an attack, a member may self-report ringing in the ears, headaches,” said General Ryder, who said there have been no other diagnoses of traumatic brain injury since then.
In March, U.S. intelligence agencies concluded that a self-destructing drone of “Iranian origin” killed a U.S. contractor and injured another contractor and five U.S. service members in an attack on a maintenance facility on a coalition base in northeast Syria.
Mr. Biden retaliated by ordering the Pentagon to carry out airstrikes against facilities in eastern Syria used by groups affiliated with the Islamic Revolutionary Guards Corps, but not the Iranian forces themselves.
Asked by reporters on Thursday when the administration would retaliate for the latest spate of attacks against American troops, General Ryder said the United States always reserves the right to self-defense. “If and when we decide to respond,” General Ryder said, “we would do so at a time and place of our choosing.”
That time came early Friday morning.