For months, Iran’s military has failed to completely close off the narrow waterway, as U.S. forces shepherd more oil tankers through, eroding Tehran’s geopolitical leverage.

Similarly, the U.S. military has failed to completely reopen the strait, as Iranian attacks on commercial vessels prevent a return to prewar traffic flows, keeping oil prices high.

But with the U.S. naval blockade also strangling Iran’s economy, Tehran was widely expected to try changing the equation with a fresh cycle of attacks—and it did.

Iran launched missiles at U.S. bases around the Persian Gulf earlier this week, then on Saturday it launched missiles at a Navy aircraft carrier and destroyer.

That prompted the U.S. military to strike three Iranian oil tankers that were deemed to be operating in the “shadow network” that funnels money to the regime’s Islamic Revolutionary Guard Corps.

“Let the message to the IRGC be clear: If you shoot at two of our ships, we will impose an even higher economic cost — taking out three of yours,” U.S. Central Command chief Adm. Brad Cooper said in a statement. “We will not hesitate to defend American forces, and if necessary, destroy Iran’s limited and exposed oil fleet.”

For Hamidreza Azizi, senior Iran analyst at the International Crisis Group, the fighting appears to represent a new phase of escalation.

Until now, Iran’s military had focused on tankers and commercial shipping around the Strait of Hormuz, he pointed out in a post on X. Meanwhile, its direct attacks on U.S. forces had been limited to bases around the Gulf.

“Attempting to strike U.S. warships enforcing the blockade therefore crosses a different threshold,” Azizi added. “The attempt failed, but there is no reason to assume the next one will. A successful strike — especially one causing significant U.S. casualties — could rapidly transform the conflict.”

Iran’s attack on U.S. warships also follows a report in the Financial Times this week that said Russia is secretly helping Iran develop supersonic cruise missiles.

A ramjet propulsion system, which would enable a missile to travel at several times the speed of sound, would likely power anti-ship and land-attack cruise missiles.

Such a weapon would force U.S. Navy ships and aircraft to move much farther away from Iran, breaking the chokehold on its economy.

For now, the naval blockade has proved to be a potent economic weapon, and Iranian officials have admitted that conditions are dire and suggested time is running out.

The Treasury Department has also vowed to inflict an “economic D-Day” on Iran with wider sanctions aimed at countries that facilitate its illicit oil trade and other financial transactions.

But Azizi warned that adding economic pressure will not necessarily make Iran more cautious, especially if Tehran sees it as unsustainable. That means the U.S. attacks on Iranian oil tankers will likely spark even more escalation.

“The greater the squeeze on Iran, the greater the incentive to act,” he wrote. “And the more Tehran comes to see that pressure as existential, the more likely it is to conclude that it has less to lose — and that increasingly risky actions are worth attempting.”