Iran’s Supreme Leader Ayatollah Ali Khamenei warned on February 2 that any American move to start a war would trigger a “regional full-scale war,” a stark reminder of how quickly rhetoric can heighten tensions in an already volatile Middle East.
The remark, delivered amid strained relations between Tehran and Washington, serves both as a deterrent and a signal to domestic and regional audiences that Iran views any military provocation by the United States as an existential threat. Khamenei’s message frames potential U.S. actions as risking a broad conflagration rather than a contained strike, shifting the rhetorical burden of escalation onto Washington.
The warning matters because Iran has deep networks of allied militias and proxies across the Levant, the Gulf and the Arabian Peninsula, and because the strategic geography of the region — from the Strait of Hormuz to Syrian airspace — allows local incidents to cascade quickly. Attacks on shipping, strikes on military facilities, or the targeting of senior commanders could prompt retaliatory strikes by Iranian-backed groups in Iraq, Lebanon and Yemen, multiplying risks for U.S. forces and partners.
Global markets and regional states are also vulnerable to such escalation. Disruption to Gulf oil exports, expanded Israeli-Iranian hostilities, or wider involvement by regional powers could drive spikes in energy prices, unsettle financial markets and force governments to recalibrate security postures. For U.S. policymakers and allies, the calculation is therefore not only military but economic and diplomatic.
Practical escalation pathways are numerous: a misattributed strike, an attack on commercial shipping, or an assassination of a proxy leader could each provoke a disproportionate response. The current rhetoric raises the political cost of kinetic action for the United States and for Israel, which has its own security calculus vis-à-vis Iran’s military and nuclear capacities.
Diplomatically, Khamenei’s statement complicates any push for de-escalation by external mediators, while underscoring Tehran’s preference for deterrence through public signalling and proxy leverage rather than direct, conventional confrontation. International actors with influence in Tehran, Washington and regional capitals face a narrow window to reduce tensions before fragile incidents escalate into wider conflict.