American forces in the Middle East are constantly under attack, but they aren't really retaliating. Here's why the US holds its fire.

• Iran-backed groups have launched dozens of attacks on US forces in Iraq and Syria since October 17.
• The drone and rocket strikes have injured a number of troops, but there's been little retaliation.
• Middle East security experts say there are a number of reasons why the US is holding its fire.

US forces stationed in the Middle East have endured a constant stream of attacks from Iran-backed groups over the past few weeks, violence that's parallel to the Israel-Hamas war but nonetheless directly related to the bloody conflict.

These attacks in Iraq and Syria — mostly carried out using small drones and rockets — have injured dozens of American service members, but the US has chosen for the most part to avoid retaliation against the culprits. Middle East security experts say that's because Washington is walking a tightrope, balancing its own strategic interests in the region with avoiding escalation while also recognizing that its enemies are doing the same, trying to intentionally provoke it without taking it too far.

American policymakers are "looking at their strategic objectives in the region and understand that adversaries are trying to pull us off of those or make those fail, including in the context of luring us into these side conflicts," Jonathan Lord, a former political military analyst at the Pentagon, told Insider.

Attacks on US forces by Iran-backed groups in the region are not a new phenomenon. Deadly exchanges have been happening for decades as a result of the Iran's longstanding desire to expel the US from the Middle East. Between President Joe Biden's inauguration in January 2021 and April 2023, Iranian proxy forces carried out 83 attacks alone, a US Central Command (CENTCOM) spokesperson previously told Insider. But attacks are occurring more frequently now.

The new wave of attacks, widely described by US officials as an "uptick," began amid swelling anger throughout the region over Israel's war against Hamas and its bombardment of the Gaza Strip, a response to the October 7 terror attacks perpetrated by Hamas against Israel. The Islamic Resistance in Iraq, which an umbrella term describing the recent operations that Iran-backed militias have conducted in Iraq and Syria, has claimed responsibility for the attacks against US forces.

A Pentagon spokesperson said on Tuesday that since October 17, there have been 40 total attacks on US forces stationed in Iraq and Syria. Independent analyses from various think tanks, including the Washington Institute for Near East Policy and the Institute for the Study of War, peg the figure slightly higher than what the Biden administration has revealed publicly because they use more inclusive methods for collecting the data.

The attacks have left at least 46 service members wounded, including 25 with traumatic brain injuries, Sabrina Singh, the deputy Pentagon press secretary, told reporters. She argued that "while we see these attacks increase, we're not seeing significant casualties or significant harm to our service members."

What's been the US response?

The Pentagon has only publicly confirmed a single incident of retaliation against the Iran-backed militias. Defense Secretary Lloyd Austin said on October 26 that the military conducted "self-defense strikes" against facilities in Syria that were used by Iran's Islamic Revolutionary Guard Corps (IRGC) and its affiliated groups.

But nearly two weeks later, the attacks on American assets have not let up. At Tuesday's media briefing, reporters pressed Singh on whether US deterrence was working and if the late-October strikes had achieved anything.

She responded that the US decides when are where it wants to retaliate, and that there doesn't need to be a tit-for-tat exchange of firepower or comparative action every time there's an attack.

"We are incredibly strategic about when we decide to take kinetic action, and you saw that on October 26," she said. "It's how successful we can be about damaging and destroying infrastructure that they have used too, and that's exactly what we did."

On a deeper level, Middle East security experts say the US knows it's not worth it to engage the militias at this moment, in part because escalation could send the entire region spiraling into utter chaos.

"If you are the US, you've made a decision that under normal circumstances, if these militias were flicking little matches at us, we'd flick two matches back every so often just because we don't want Americans to get killed," Michael Knights, the co-founder of the Militia Spotlight platform at the Washington Institute, told Insider.

"Weirdly, under these circumstances, we are saying, 'Listen, we're sitting on a powder keg that's under everyone's house, and it doesn't matter if they flick matches at us, we're not going to flick matches back at them because we are not that irresponsible," Knights said.

An underlying fear in the US and Israel is that the war with Hamas could expand into a regional conflict, drawing in Iran or its proxies in a more direct role. To some extent, this is already the case. Lebanon's Hezbollah regularly exchanges fire with the Israeli military, Houthi rebels in Yemen have launched missiles and drones at southern Israel, and the Islamic Resistance in Iraq continues to attack American assets.

But the Biden administration also appears to be looking at these attacks and choosing to ignore them, for the most part, because it's not necessarily seeing a strong push by the militias to inflict maximum causalities on US forces or overwhelm their defensive systems, Knights said. In other words, these groups are not trying their hardest.

Before Israel's war with Hamas, such attacks might realistically only lead to a localized tit-for-tat exchange of firepower, like what happened in March after an American contractor was killed when an Iranian drone hit a base in Syria. "But in this circumstance," Knights said, "you could trip off a Hezbollah-Iran-Israel war."

A high-stakes balancing act

Escalation against US forces doesn't work on a binary scale where all of the sudden these groups just decide to go all in on attacks, said Lord, the director of the Middle East Security program at the Center for a New American Security think tank. Their activities are calibrated based on their own political goals.

Attacks against US forces, for example, could help boost the militias' credentials against competitors and hamstring US operations in Iraq and Syria, where around 3,500 troops remain to help defeat the Islamic State. And with tensions boiling throughout the region amid Israel's war with Hamas, the Iran-backed militias are choosing now as their time to escalate, Lord said. But Washington isn't taking the bait.

"I think US policymakers are trying to balance defensive responses that effectively demonstrate US capabilities to protect its people, while also keeping on the balance beam of walking towards those strategic goals that include the defeat of ISIS," Lord said. "In this case, another important goal that's been thrown on the board is not seeing regional conflicts with Iran proxies escalate or expand the conflict going on in Gaza."

Indeed, crushing ISIS has long remained a focus of the US military, but in the wake of the Israel-Hamas war, the Pentagon has outlined four new objectives in the Middle East: protecting American forces and citizens, outfitting Israel with security assistance, securing the release of hostages held by Hamas, and preventing the war from spreading beyond Gaza.

Right now, US officials stress that deterrence — signaled by the massive movement of American combat power into the region — is working, and the Iran-backed attacks on American forces have been unsuccessful. Future retaliation is not off the table, but at this moment, the military doesn't seem to believe that it's needed.

"The policymakers are trying to keep their heads above the emotional level to keep us focused and moving towards those broader objectives that prevent wider conflict," Lord said, "and in the end, likely will serve to save us lives."