The article argues that President Trump’s policy change towards Iran—and the Middle East more broadly—during his first term was motivated by a shift in external structural conditions caused by his predecessor’s policy. More specifically, President Obama’s signature of the Joint Comprehensive Plan of Action (JCPOA)—commonly known as the ‘Iran nuclear agreement’—amid his Middle East policy led to a change in the external environment that was perceived by President Trump as an external threat from a domestic point of view. The change in the external environment led to a change in foreign policy with domestic-level factors intervening between the external driver and the strategic response. From an international relations theory perspective, the idea that great powers can induce shifts in the regional distribution of power that create threats at a systemic level and that individual states adjust their foreign policy behaviours to systemic outcomes is consistent with the neoclassical realist framework. The article also confronts Trump’s Middle East policy with Obama’s arguing that, apart from different styles, both presidents essentially adopted different tactics to pursue U.S. interests.