Iran has brought days of relative calm in the Middle East to an end after launching what the US called a "surprise" attack in a striking change to the pattern of fighting.

Rather than responding to a fresh American strike, Tehran chose to restart the fight itself, showing a growing willingness to use military force to shape the course of the war on its own terms.

This in turn sets the stage for fresh escalation. "We are going to beat the f**king sh*t out of them," US President Donald Trump told Fox News Wednesday morning. "We'll be hitting them hard. They're going to get a beating."

That threat could hardly have surprised Tehran, which launched its missiles knowing they might bring US bombers back.

Trump had attributed last week's pause to a request from Iran because "they asked us very nicely" and wanted talks. Tehran never publicly committed to the recent pause, although a senior Iranian official said "our armed forces also decided not to take military action."

That makes Iran's decision to resume fire all the more significant.

Hours after publicly signaling that it would match the US restraint, Tehran targeted American forces – apparently deciding that raising the pressure was worth the risk of restarting the nightly bombardment.

"Something appears to have changed fundamentally in Iran's approach, particularly regarding its willingness to initiate a strike if it considers that to be the only viable option," Hamid Reza Azizi, a researcher at the German Institute for International and Security Affairs, wrote on X.

US President Donald Trump, right, meets Israeli Prime Minister Benjamin Netanyahu at White House on Tuesday. - MaΓ’ayan Toaf/GPO/Anadolu/Getty Images

Iran's strike came soon after Israeli Prime Minister Benjamin Netanyahu's meeting with Trump in Washington, DC, which the Israeli leader described as "one of the best conversations" the two have had following growing friction between the pair. Hours before the meeting, Israeli Defense Minister Israel Katz said Israel had wanted to strike Iranian energy infrastructure but had been held back by the Trump administration.

"The attack appears to have been a signal related to Netanyahu's visit to the White House earlier in the day," wrote Azizi. "It suggests that Iran's military strategy may have changed and that Tehran is now prepared to launch a preemptive strike if it detects signs of an imminent threat."

Shortly after the attack in Jordan, the US and Saudi militaries jointly struck Iran-backed militias in Iraq. US Central Command framed the Iraq operation not as retaliation for the Jordan attack, but as a response to more than 30 drone attacks against US forces and Saudi energy infrastructure over the previous 72 hours.

The overnight escalation showed how the war is widening. Saudi Arabia, long wary of being pulled directly into the conflict, is becoming more deeply involved as it faces threats on three fronts: the Houthis in Yemen, Iran-backed militias in Iraq, and Iran itself.

Damage at a site belonging to Iraq's Popular Mobilization Forces (PMF) following airstrikes that the PMF said were carried out by US and Saudi forces, in Bartella, Nineveh province, Iraq, on Wednesday. - Khalid Al-Mousily/Reuters

"The central challenge facing Washington and its Gulf partners is that neither Iran nor its regional allies appear willing to retreat from what they now define as core strategic objectives," Danny Citrinowicz, a senior researcher at Israel's Institute for National Security Studies and a former head of the Iran branch in Israeli military intelligence, wrote on X.

"Tehran continues to insist on maintaining its leverage over the Strait of Hormuz, while the Houthis have made clear that they will not end their campaign unless the Saudi-led (blockade) imposed on them (is) lifted."

In an interview with Iranian state television published just hours before the attack in Jordan, Deputy Foreign Minister Kazem Gharibabadi offered perhaps one of the clearest articulations of Tehran's position yet. Iran had stopped firing, he suggested, but would not hesitate to resume hostilities if its claim of sovereignty over the Strait of Hormuz was challenged.

Tehran could not consider itself victorious if the strait returned to its prewar status, the deputy foreign minister said. The waterway had become central to the country's national security and a "defensive tool."

When the interviewer asked why Tehran had risked restarting the war by attacking commercial ships despite a functioning ceasefire, Gharibabadi said Iran regarded efforts by Oman and the US to establish a rival shipping route through the strait as a red line. Allowing that route to operate, he argued, would have reduced Iran's claim to the "effective exercise of sovereignty" over the waterway to "nothing more than a fantasy."

"One might look at it simply and ask why Iran would hit three commercial ships with missiles just because they turned off their GPS, potentially restarting a war," he said. "But if you look behind the scenes, you see that the arrangements applied to the Strait of Hormuz will have a long-term impact on the security of the Islamic Republic of Iran."

From Tehran's perspective, Washington's pause in attacks on Iran reflects "strategic weakness rather than restraint," Citrinowicz wrote. That perception risks fueling a cycle in which Iran escalates to impose greater costs, while neither side backs down for fear of losing credibility.

The US and its partners therefore face a choice, he argued: accommodate some Iranian demands, or accept the prospect of a prolonged conflict marked by mounting attacks on shipping, energy infrastructure and trade routes.

Aida Karimi, Eyad Kourdi, Dana Karni, Mohammed Tawfeeq and Tal Shalev contributed to this report.

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