Despite the odd angle used throughout all the western media propaganda. It was an Iraqi group not Iranian group. The constant push to frame this as "USA vs. Iran" by calling it an Iran-backed group, instead of an Iraqi group, or be specific and state that it was "Islamic Resistance in Iraq" is just befuddling. It's like if the media was covering the current crisis in Palestine/Israel, while never mentioning Israel and instead writing headlines like "USA-backed group bombs hospital in Gaza".
As for why this Iraqi group is able to attack USA, it's likely much more to do with the 13 year old failed US Invasion of Iraq than anything to do with Iran. But It feels like USA is embarrassed enough about that whole thing that they have decided to just ignore that Iraq exists and instead consider this to be an attack all along the Jordan-Iran border, which for anyone geographically interested is just as long as the border between USA and France.
As for why this Iraqi group is able to attack USA, it's likely much more to do with the 13 year old failed US Invasion of Iraq than anything to do with Iran. But It feels like USA is embarrassed enough about that whole thing that they have decided to just ignore that Iraq exists and instead consider this to be an attack all along the Jordan-Iran border, which for anyone geographically interested is just as long as the border between USA and France.