This article examines the geopolitical, economic, commercial, and security implications of the rebranding and redefinition of the Zangezur Corridor within the framework of the 8 August 2025 peace agreement between Armenia and Azerbaijan, mediated by the United States. Referred to as the “Trump Route for International Peace and Prosperity,” the project involves a 32-kilometre connection through Armenia’s Syunik Province and the possible long-term management or lease of the route by the United States. Focusing on the interests and concerns of Azerbaijan, Armenia, the United States, Iran, Türkiye, and Russia, the study argues that the corridor could generate significant economic benefits by strengthening east–west connectivity, expanding the Middle Corridor, diversifying energy routes, and facilitating Eurasian trade. However, these benefits are likely to be distributed asymmetrically. From Iran’s perspective, the project may constrain the country’s northern access to Europe and the Black Sea, reduce transit revenues, and increase border-related security risks. Consequently, Tehran may interpret the corridor as part of a broader geopolitical strategy of pressure and containment. The initiative could also weaken Russia’s traditional mediating role in the South Caucasus while enhancing the strategic presence of the United States and NATO. After reviewing the historical roots of the dispute and its intensification following the 2020 Nagorno-Karabakh war, the article proposes that Iran pursue alternatives such as developing the Aras Corridor, strengthening the International North–South Transport Corridor, and employing multilateral diplomacy. The findings emphasize the need for inclusive regional arrangements to prevent escalation, reduce insecurity, and promote balanced development.