Joint Chiefs Chairman Caine commits the U.S. military to seizing Iran-linked vessels worldwide

At an April 16, 2026 Pentagon press briefing, Chairman of the Joint Chiefs of Staff Gen. Dan Caine publicly committed U.S. forces to "actively pursue any Iranian-flagged vessel or any vessel attempting to provide material support to Iran," explicitly including dark-fleet oil carriers. Caine and Secretary of Defense Pete Hegseth described a naval blockade of Iran -- imposed on April 13 -- that now covered the Gulf of Oman, the Arabian Sea east of the Strait of Hormuz, the entirety of the Iranian coast, and the U.S. Indo-Pacific Command area of responsibility. The Pentagon said any vessel suspected of trying to reach Iranian territory would be subject to visit, board, search and seizure regardless of its location. By April 16, 13 vessels had been turned back; CENTCOM put the figure at 23 by April 18.

The expansion advanced what Treasury Secretary Scott Bessent, on April 15, named the "Economic Fury" phase of the pressure campaign -- which he called "the financial equivalent of what we saw in the kinetic activities." On April 18 the Wall Street Journal reported that the military was preparing to board and seize Iran-linked commercial ships in international waters in the coming days, reporting corroborated by subsequent independent coverage. Hegseth told the briefing the blockade would continue "as long as it takes" and warned of "bombs dropping on infrastructure, power and energy" if Tehran "chooses poorly."

The Iran war began on February 28, 2026 without a congressional declaration of war or an authorization for use of military force. The War Powers Resolution requires the President to terminate unauthorized hostilities within 60 days of notifying Congress (with a single 30-day extension for safe withdrawal) -- a clock that, by Caine's April 16 commitment, was within roughly two weeks of expiry. The Senate has invoked the War Powers Resolution four times since February; Republican leadership blocked each attempt. What places this briefing in the archive is constitutional rather than operational: the executive branch publicly extended and escalated an unauthorized war -- adding the Pacific theater, defining the whole Iranian coast as in-scope, and threatening seizure in international waters -- while framing the campaign as a coercive economic instrument. The public commitment of the uniformed military to that political-coercion framing, narrated by the Joint Chiefs Chairman alongside the "Economic Fury" branding, is recorded here under executive overreach, bypassing Congress, and the politicization of the uniformed services.