Although Iran does not border the Bab al-Mandeb Strait, Yemen does, and Iran is closely allied with the Houthis, the Yemeni militant group that previously conducted dozens of strikes against Israel-linked vessels in the Red Sea in 2023 and 2024 in response to the war in Gaza.
Random innocent ship crews aren’t being targeted, ships that provide oil to Israel and US forces are, they directly support the terrorism done by these regimes. It’s like saying “what you are doing supports the inhuman war against my people, the fuel you sell to the genociding army provides the power for their planes to bomb our schools and massacre our children. We will stop ships from supporting this war effort, you can willingly leave your ship or we will disable it.”