Can US reinforcements in the Middle East deter Iran's next strike on Israel?

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The US has completed a deployment of B-52 bombers and F-15E fighter-bombers to the Middle East, while additional warships are en route to the region, ahead of the next expected flare-up of violence between Iran and Israel.

It is feared the latest clashes could drag in US forces after threats by Iran-backed militias in Iraq to escalate against them, possibly using Iraqi soil for missile strikes on Israel.

The deployment comes on US election day, when some fear Iran might strike before the formation of the next government and any clear policy from Washington on the crisis. Pentagon spokesman Air Force Maj Gen Patrick Ryder said the deployment was specifically aimed at deterring Iran “and its partners”.

According to Farzin Nadhimi, an expert at the Washington Institute for Near East Policy think tank, Iran’s promised retaliation for Israel’s October 26 air strike could occur on Tuesday and comprise hundreds more ballistic missiles aimed at “disabling major Israeli air bases”, he wrote on social media platform X.

Security sources told The Jerusalem Post that Israel had “reinforced its detection, warning, air defence, intelligence and operational systems”.

“The military build-up of American air assets in US Centcom’s area of operation aligns with previous US moves to strengthen its deterrent posture and counterstrike capability, including deploying THAAD batteries and aircraft carrier strike groups,” says Leonardo Jacopo Maria Mazzucco, an independent expert on Middle East security.

“However, deploying additional forces has so far failed to achieve its core goals: restoring deterrence and dissuading Iran from climbing the escalation ladder. From a US standpoint, the pre-positioning of F-15 aircraft and B-52 strategic bombers in the Middle East serves symbolic and tactical ends. On the symbolic level, it represents Washington's umpteenth effort to reinforce a shaky deterrence equation with Iran and the members of the Tehran-backed ‘Axis of Resistance',” says Mr Mazzucco.

Wider conflict

Iran-allied Iraqi militias in the Popular Mobilisation Forces (PMF) are expected to join the assault, possibly leading to Israeli counterstrikes there, although the groups launch many attacks from Syria as part of the “Axis of Resistance”, which includes Hezbollah in Lebanon and the Houthis in Yemen.

The Iraqi militias have also issued threats against US bases in Iraq, with Ali Al Asadi, the spokesman for Hezbollah Harakat Al Nujaba – one of the most radical factions – renewing threats to US forces in Iraq. The group is part of the Islamic Resistance, a coalition within the PMF formed after the start of the October 7 Israel-Gaza war.

Attacks on US forces by the group have on occasion provoked US counter strikes, including a wave of 85 air strikes in February which killed and injured scores of PMF fighters, following a deadly drone strike on US forces in Jordan the previous mont claimed by the factions.

The US is now primed for what Centcom calls self-defensive strikes, with the B-52s capable of carrying 20 stealthy AGM-158 cruise missiles with a 1,000km range, last used in a barrage against Syria in 2018. The US has sent six of the aircraft.

F-15Es are known for their ability as fighters, including high manoeuvrability, but can also carry up to 15 precision bombs. They join another squadron that deployed in September, alongside squadrons of A-10 Warthogs and F-16s. Each squadron has roughly 12 aircraft, but while the US has disclosed reinforcements, there is no detail on current totals in the region.

The deployments come while the US has no aircraft carrier in the region, amid operations in the Pacific and scheduled maintenance of the ships that represent Washington’s most powerful offshore strike capability.

Experts have highlighted how A-10s could use their guns, capable of firing nearly 4,000 cannon rounds per minute, against Iranian attack boats which might “swarm” US ships in a conflict.

The deployments signal that the US is accutely aware of its vulnerabilities in the region.

"There’s a strong possibility that Iran’s response could be one of its most consequential actions against Israel yet, potentially escalating tensions in a dangerous new direction. If Iran decides to launch a significant series of ballistic missile attacks to weaken Israeli Air Force (IAF) infrastructure or operational capacity — as Israel has degraded Iran’s air defense and missile capabilities in their recent strikes — this could trigger an intense cycle of retaliatory strikes," says Freddy Khoueiry, Global Security Analyst for the Middle East and North Africa at RANE Risk Intelligence.

"Given Israel’s likely response, matching or even exceeding the force of Iran's actions, a sustained conflict of escalation could quickly unfold. This time, Iran appears to be strategically focusing on reducing Israel’s capabilities including its air power, rather than just inflicting limited physical damage on air bases, as a way to reestablish deterrence," he says.

An escalation on that scale would create a serious security dilemma for the US, Mr Mazzuco says.

“On the tactical dimension, the US is responding to the imperative of being prepared should Israel-Iran escalation reach new heights or, worse, conflagrate into an all-out war."

“As forward-deployed assets alone cannot rebuild deterrence, they should be meaningfully supported by back-channel negotiations. The fact that Israel's October 26 air military operation did not target Iranian energy and nuclear facilities but was limited to military sites suggests that the US still retains some capacity to pressure belligerent parties to keep the conflict at the lower ends of the escalation ladder.”

He warns however, that if the current reinforcements fail to deter Iran, Washington will need to muster more forces “to nudge the Middle East region away from the abyss of war”. This will pose a fresh challenge to Washington ahead of post-election government formation, especially since there is not a strong appetite for deeper US involvement in the regional war.