Israel and the US launched a war against Iran based on strategic convergences around regime change, degradation of Iran’s nuclear, military and missile capabilities, and non-state networks. The failure to achieve these objectives alongside Iran’s blockade on the Strait of Hormuz, retaliatory strikes on Gulf states and the ability to influence Lebanon’s future, exposed differences between Israel and the US over the means, timing and acceptable costs of pursuing the said goals.

Following the 17 June 2026 Memorandum of Understanding (MoU) between Washington and Tehran, the US restrained Israel’s direct involvement in Iran, limiting its role to intelligence cooperation and allowing calibrated military efforts in Lebanon to weaken Hezbollah. Israeli Prime Minister Benjamin Netanyahu noted that joint military efforts succeeded in deterring Iran’s immediate nuclear threat, severely damaging Iran’s missiles, military and non-state networks and vowed to hold security zones in Lebanon, Gaza and Syria indefinitely to ensure the Jewish state’s security.[1]

The US has pressed for diplomacy over the nuclear issue while continuing its war of attrition against Iran, with the battleground shifting to the Strait of Hormuz amid disputes over control of the vital waterway, triggering renewed strikes targeting military and critical infrastructure.[2] Israel welcomed the MoU’s collapse, advocating continued full-scale joint war efforts to translate military gains into strategic outcomes. Therefore, the war has reflected divergences in interpretation of the Iranian challenge between Israel and the US over Lebanon, the Strait of Hormuz, and the nuclear and missile programme.[3]

US’ Changing Priorities

President Donald Trump, after launching the war, anticipated a swift and decisive victory, seeking access to its oil and other resources, influence over Iran’s leadership transition, and cultivation of pro-Western ‘moderates’ favouring change from within the Islamic regime to avoid a power vacuum, instability or civil war.[4] In the absence of decisive victory, Washington pursued containment, deterrence, coercive diplomacy and strategic bargaining, combining military, economic and political pressure, including infrastructure disruption, sanctions and phased concessions, diplomatic timelines and inspections, to compel renewed negotiations over ceasefires, maritime access and the nuclear programme.[5]

Washington situates Iran within a broader strategic environment, assessing the potential costs across other theatres and dynamics involving China, Russia and its Gulf allies.[6] Therefore, Washington seeks to avoid prolonged, large-scale military engagement, particularly ground operations amid the upcoming mid-term elections, Congressional scrutiny, budgetary pressures costing US$ 45.1 billion between 28 February and mid-September 2026 and public opposition, including from Trump’s Make America Great Again (MAGA) base, to new wars.[7] Rising perceptions that Trump was manipulated into a costly “war of choice” have reframed the Netanyahu government as a liability, intensifying demands to re-assess military aid to Israel.[8]

Trump’s military objectives evolved from regime change and unconditional surrender to securing the Strait of Hormuz and nuclear non-proliferation, creating ambiguity that enabled him to declare victory despite a lack of transformational change.[9] Nevertheless, the failure compelled Washington to prioritise containing the conflict’s spillover, particularly by reopening the Strait of Hormuz, preserving global oil market stability and deterring retaliation against the energy facilities of the Gulf States.[10] Disruptions to international shipping, which have heightened inflationary pressures, have pushed Brent crude prices above US$ 100 per barrel. The tensions over the Strait of Hormuz and Iran’s retaliatory attacks on US allies have undermined Washington’s power projection, testing the reliability of its security guarantees and ability to safeguard maritime access.

The war has reduced Iran’s incentives to offer nuclear concessions as the naval blockade strengthens its bargaining position, and preserving nuclear capabilities provides a potential deterrent in the future. The US........

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