Attacks on US Citizens - even those in Israel - sponsored by Iran IS an attack on the US.

Terror attacks by Iran on US troops fighting in Iraq count too. Here's more:

During the Iraq War, the Quds Force, an elite unit of Iran’s Islamic Revolutionary Guard Corps (IRGC), was widely reported to have supplied Shiite militias with EFPs—a particularly lethal type of roadside bomb. These devices were capable of piercing armored vehicles, and their use led to the deaths and injuries of hundreds of U.S. troops.
- EFPs were precision-engineered, often with copper liners, and required advanced manufacturing—something U.S. intelligence believed pointed to Iranian state support.
- The Quds Force also provided training and funding to groups like Kata'ib Hezbollah and the Mahdi Army, enhancing their ability to carry out sophisticated ambushes and attacks.
This support was part of Iran’s broader strategy to undermine U.S. influence in Iraq while maintaining plausible deniability.

https://www.iranwatch.org/iranian-entities/irgc-quds-force