If you’re curious as to why Iran might’ve decided to target commercial vessels in the Strait of Hormuz earlier this week at considerable risk of inviting retaliatory US attacks, the answer goes something like this.

Amid snail’s-pace negotiations ostensibly aimed at coming to mutually agreeable terms on the future of the Iranian nuclear program, the Pentagon was actively engaged in an effort to help oil and gas tankers evade the IRGC’s newly-established toll authority in the waterway.

Specifically, the Guards determined that the US Navy was directing local maritime traffic along a route that hugged the Omani coast and didn’t require vessels to check with, let alone pay fees to, the IRGC’s so-called Persian Gulf Strait Authority.

Iran still believes it can monetize the Strait in perpetuity via the jointly-run scheme with Oman, which would compel ships to make payments for “safe passage permits” — services rendered, as it were.

I think that’s hopelessly naive, almost to the point of being pitiable, but the Guards believe it. And the fact that traffic through the Strait had returned to about a third of pre-war levels presumably without enriching Tehran angered the IRGC, so they lashed out.

That’s one version of the events which led to this week’s fireworks. Another says Iran’s concerned that a US-brokered deal to end the fighting in Lebanon might actually succeed in disarming Hezbollah.

I don’t see how that’s possible, but apparently, Tehran’s not satisfied with the structure of the nascent arrangement between Israel and the Lebanese government. Hezbollah’s a part of that government but hasn’t been actively engaged in the peace process.

Whatever the case, Iran and the US traded strikes again on Thursday just hours after Donald Trump made a series of disparaging remarks about the Guards (who he called “scum”) accompanied by bombastic threats to seize Kharg Island and strike Iran’s desalination plants.

Centcom said the US military struck dozens of sites in Iran “to further degrade [the Guard’s] ability to attack commercial shipping.” It’s all about protecting “innocent civilian mariners,” the Pentagon insists.

For its part, Iranian state media said Thursday’s American strikes destroyed (or at least damaged) two bridges and disrupted traffic on a rail line between Tehran and Mashhad. In retaliation, the IRGC did what the IRGC does: Fired missiles and dispatched drones at US bases in Kuwait and Bahrain, where no one was killed.

Iran’s health ministry was still counting its dead, but the initial tally put the two-day death toll in Iran at 14. Dozens were wounded in two days of American strikes. The international community has no means by which to assess those claims.

Trump said Iran called him to stop the fighting. “They want to make a deal so badly,” he told reporters. No one believed him.

The New York Times quoted Suzanne Maloney, a former Mideast policy advisor to both Republican and Democratic administrations. “[T]he timing of the attacks, coinciding with [Ali Khamenei’s] funeral ceremonies, demonstrates a bit of triumphalism on the part of the regime,” she said. “They’re able to bury their dead, and they’re still firing back.”