Remarkable in some ways, but not completely unusual. Iranian and American forces have jousted with each other in the Persian Gulf for years, if not decades, as part of the tension between the two nations since the 1979 Islamic revolution. Occasionally it makes news in a bad way, such as the capture of ten US sailors by Iran early last year, or when Iran’s proxies fire at our ships. Sometimes it looks better, as when we fire across Iranian bows.

We don’t always get video, though, which makes this a little more interesting:

A U.S. Navy patrol boat fired warning shots Tuesday near an Iranian vessel that American sailors said came dangerously close to them during a tense encounter in the Persian Gulf. Iran’s hard-line Revolutionary Guard later blamed the American ship for provoking the incident.

The encounter involving the USS Thunderbolt, a Cyclone-class patrol ship based in Bahrain as part of the U.S. Navy’s 5th Fleet, is the latest confrontation between Iranian vessels and American warships.

The Thunderbolt was taking part in an exercise with American and other coalition vessels in international waters when the Iranian patrol boat approached it, 5th Fleet spokesman Lt. Ian McConnaughey said. The Iranian ship did not respond to radio calls, flares and horn blasts as it came within 150 yards of the Thunderbolt, forcing the U.S. sailors aboard to fire the warning shots, McConnaughey said.

“After the warning shots were fired, the Iranian vessel halted its unsafe approach,” the lieutenant said in a statement, adding that the Iranian vessel created “a risk for collision.” Large ships can’t stop immediately on the water, meaning getting close to each other risks a collision.

It’s not entirely SOP for US ships to fire at Iranian vessels, The Atlantic’s Aria Bendix argues. She links this incident to Donald Trump’s warnings to Tehran, most recently at the Youngstown rally yesterday:

While it’s common for U.S. and Iranian ships to come within close proximity of one another in the Persian Gulf, it’s far less common for the U.S. to issue a warning shot. In April, an Iranian military ship that came within 1,000 yards of the U.S.S. Mahan was accused of “unprofessional” and “provocative” conduct, but did not elicit any fire from the U.S. Aside from Tuesday, the last major conflict between U.S. and Iranian ships occurred in January, when the Mahan fired three warning shots at an approaching fleet of Iranian vessels. Before that, the U.S.S. Squall fired multiple warning shots into the water after an Iranian boat came within 200 yards of it in August 2016.

Tuesday’s incident marks the closest encounter between a U.S. ship and Iranian vessel in the Persian Gulf in at least a year. The incident comes a week after the U.S. slapped a new round of sanctions on Iran over its ballistic-missile program. A day before the sanctions, President Trump certified that Iran was in compliance with a 2015 nuclear agreement with the U.S. and other world powers. Under the agreement, the U.S. administration must inform Congress of the status of Iran’s nuclear program every 90 days. Trump has previously called the deal “the worst” ever and expressed doubts over whether Iran will continue to comply.

At a Tuesday night speech in Youngstown, Ohio, Trump warned Iran that it could face “big, big problems” if it failed to conform to the terms of the deal. Telling the crowd that Iran had become “emboldened” by the agreement, Trump repeated a pattern of issuing advisories to Iran at his rallies. At a campaign event last year in Pensacola, Florida, Trump directly referenced the close encounters between U.S. and Iranian ships in the Persian Gulf, telling supporters that when the Iranian military “circle[s] our beautiful destroyers with their little boats … they will be shot out of the water.”

There’s no better way to emphasize that with a little show-and-tell. Trump promised to ease engagement restrictions in war zones, and while the Persian Gulf doesn’t quite qualify as such, Iran has been known to test our limits. Perhaps a few shots across the bows of their craft will dial down that aggressiveness before carelessness provokes a shooting war in the Gulf.