The United States has begun a maritime blockade of Iran targeting the Strait of Hormuz. It is a strategy to squeeze Iran in response to its "strait control card."
U.S. President Donald Trump said on the 13th local time at the White House that "as of 10 a.m., we have begun a maritime blockade against Iran." According to the Wall Street Journal (WSJ), the U.S. military deployed more than 15 warships around the Strait of Hormuz for this operation. Since the 11th, U.S. Aegis destroyers, including USS Frank E. Petersen and USS Michael Murphy, had already moved into the strait.
The U.S. blockade targets all vessels entering and leaving Iranian ports and coastal areas. U.S. Central Command warned that "vessels entering or departing the blockade zone without U.S. military authorization will be subject to interception, diversion, and seizure." Trump also said on the social media platform Truth Social that "we have already destroyed 158 Iranian naval vessels," adding, "any remaining fast boats that approach the blockade zone will be removed immediately." However, the position is that vessels from countries other than Iran may transit the Strait of Hormuz if they use third-country ports.
The move came immediately after U.S.-Iran armistice talks in Islamabad, Pakistan, on the 11th–12th fell apart. The two sides had agreed to a two-week truce earlier, but tensions rose again as Iran continued to control the strait. The U.S. action is seen as intended to weaken Iran's war-fighting capability by simultaneously blocking its crude oil exports and the inflow of military supplies. At the same time, it is calculated to neutralize the "strait blockade threat" Iran has used in negotiations.
Iran pushed back immediately. Mohammad Bagher Ghalibaf, speaker of Iran's parliament and head of the delegation in talks with the United States, warned of a hard-line response in a statement the previous day aimed at Trump, saying, "If you fight, we will also fight." The Islamic Revolutionary Guard Corps (IRGC) also hinted at the possibility of a military response.
Accordingly, some analysts say the likelihood of a renewed physical clash between the U.S. and Iran in the Strait of Hormuz has grown. In particular, if the truce period remaining until the 21st is neutralized, there is speculation that the war could enter a "second round" of escalation.
Some suggest the U.S. blockade may be a "pressure card" to increase leverage rather than a step toward military confrontation. In fact, Trump said at the White House while meeting with reporters that "we have been contacted by the other side (Iran), and Iran very much wants an agreement."