A Patriot missile is launched as part of the Patriot Air Defense System at White Sands Missile Range in New Mexico. | Corbis via Getty ImagesThis story appeared in Today, Explained, a daily newsletter that helps you understand the most compelling news and stories of the day. Subscribe here.President Donald Trump’s on-again, off-again war with Iran is officially on again. (So recursive is this never-ending conflict, in fact, that I had to search my inbox to confirm I hadn’t already written that sentence!)On Sunday, the US attacked rocket launchers Sunday on Iran’s Larak Island, claiming the strikes were necessary to prevent Iran from laying mines that could once again disrupt shipping through the Strait of Hormuz. Iran, meanwhile, responded by firing a volley of ballistic missiles at US sites in the United Arab Emirates and Jordan, where they were reportedly intercepted. The latest skirmish comes after a month of relative peace and quiet, and six months after the war began. You’ll recall that Trump initially said it would last four to five weeks at the very longest. But in the grand scheme of Trump’s Iran fictions, that optimistic timeline isn’t even the most flagrant. On Sunday night, the president also posted a video that purportedly showed Kharg Island, a central hub of Iran’s oil industry, “being blown to smithereens!!!” The video was, in fact, AI-generated. Go a little deeperView LinkThe persistence of the war in Iran isn’t merely exhausting for those of us following along at home. As a group of high-ranking military commanders recently warned the Pentagon, the drawn-out conflict could also make America less safe by limiting the military’s ability to respond to threats in other parts of the world. That unusual warning — first reported over the weekend by the Washington Post — suggested that the war in Iran is tying up ships and surveillance planes that the US needs elsewhere. Several top military leaders explicitly warned that the war had forced them to give up resources they needed to protect the US itself. That’s not the only risk of the ongoing conflict, either. Longer deployments have also eroded troop morale and disrupted ship maintenance. And as the war drags on, the US is burning through its stockpiles of advanced missiles, at a cost of many billions of dollars. None of this means we’re defenseless, of course. But the war in Iran is taking up a lot of bandwidth. And should another conflict break out anywhere else on earth…the US and its allies could feel it. One general warned the Pentagon that, without more resources, he could be forced to choose between protecting Israel and the US from ballistic missile attacks. And the Navy just moved its only dedicated aircraft carrier in the Pacific to the waters near Iran. “We are really robbing Peter to pay Paul,” one military expert told Vox in late February, even before we had any idea how long the war would last.One link for later➨ Ditch the doorbell camera. More than 62 percent of respondents in a recent US News survey said they had an outdoor security camera at home. But there’s not much evidence that those cameras reduce crime — and they can damage your relationship with your neighbors. Before you go… Did you know…that the known world basically ended around 1200 BCE? A number of sophisticated civilizations collapsed at the same time, probably due to some combination of prolonged drought, earthquakes, migration, war and political instability.Today’s trivia: What was the name of Japan’s capital city before it was renamed Tokyo? (You can find this and other brain puzzles in Vox’s daily crossword. Look for the answer in tomorrow’s edition.)Yesterday’s trivia: Last week we asked you for the name of the athletic conference where Georgia Tech competes. That would be the ACC, or Atlantic Coast Conference, which confusingly includes a number of schools in the West and Midwest.