On July 16, 2026, the United States expanded its military campaign against Iran into northern Iran and stopped a ship that was trying to break through a U.S. blockade in the Strait of Hormuz, according to Britannica. The escalation follows days of U.S. strikes and Iranian retaliation across the region.

This crisis did not come out of nowhere. In June 2026, the White House announced a deal with Iran stating that Iran will never obtain a nuclear weapon and that the agreement reopens the Strait of Hormuz to free navigation, according to a White House release dated June 19. Secretary of State Marco Rubio said the U.S. lifted oil sanctions — penalties meant to pressure Iran by cutting off its ability to sell oil — and that Iran, Iraq, and a group of Gulf countries called the GCC would negotiate over the Strait. Rubio also said: "We're going to give diplomacy every chance to work."

That deal came after an earlier ceasefire. According to the U.S. State Department, following U.S. strikes on Iran in June 2025, both sides paused fighting so diplomats could address Iran's nuclear program. Those June 2025 strikes targeted Iran's Fordow Fuel Enrichment Plant using 30,000-pound bombs designed to punch deep underground. The Department of Defense called the operation a "historically successful" strike 15 years in the making.

The ceasefire started to fall apart in July 2026. On July 7, Iran sent a letter to the UN Security Council saying U.S. forces had struck over 80 targets in Iran, according to IRNA. Reuters reported on July 14 that the U.S. military had carried out a third straight night of strikes. On July 15, the U.S. launched two waves of attacks on Iran's coastal defenses and missile sites. President Donald J. Trump gave an update on the retaliatory strikes on July 8.

The Strait of Hormuz is a narrow waterway between Iran and Oman. About a fifth of the world's daily oil supply passes through it. It has become the center of this conflict. On July 11, Iran declared the Strait closed to ships it had not authorized and expanded attacks on Gulf states after U.S. strikes, according to Reuters. On or around July 13, President Trump said the Strait is open and will stay open with or without Iran, and that the U.S. is reinstating "the Iranian blockade." Iran's government said on July 9 that foreigners have no stake in the Strait and warned the U.S. about interfering with shipping. On July 14, an Iranian Army spokesperson said Iran's armed forces would not compromise on Iran's rights in the Strait. On July 16, Iran called the Strait an "unbreakable red line," according to CNN. Iran also warned it would target regional infrastructure if the U.S. carried out strikes, Reuters reported the same day.

Iran has backed up its words with military action. On July 14, Iranian forces used drones and missiles to attack U.S. bases in the region, according to IRNA. The IRGC, which is an elite branch of Iran's military, said a second vessel was hit in the Strait in an incident involving the U.S. on or around July 14. Iranian government spokesperson Fatemeh Mohajerani said U.S. attacks on Iran violate international law and basic humanitarian values.

Gulf states have been willing to overlook problems in the U.S.-Iran ceasefire agreement as of July 16, according to CNN, because the immediate danger from fighting in the Strait feels more urgent than fixing the deal. Meanwhile, the New York Times reported on July 16 that the hostilities between the U.S. and Iran have left Israel in an uneasy limbo.

The broader context here involves a system of sanctions and tariffs that existed before the June deal. In February 2026, President Trump signed an Executive Order reaffirming a national emergency with respect to Iran. The White House issued a fact sheet saying the order set up a way to impose tariffs — taxes on trade — on countries that do business with Iran. That tool is still available even though the June agreement tried to shift toward diplomacy.

The expansion of strikes into northern Iran suggests the U.S. is going after a wider range of targets, not just coastal and nuclear sites. At the same time, the arrangement to keep the Strait of Hormuz open has collapsed, and the negotiations Rubio described in June now appear to have been overtaken by actual fighting. Iran is threatening to target regional infrastructure, and the U.S. is back in a blockade posture. The gap between the diplomatic plan from June and the reality on the ground in July keeps growing. Gulf states are willing to accept the flawed ceasefire because their top priority is calming the maritime threat, but Iran's military leaders have shown no sign of backing down on what they call their rights in the Strait.