A partial breakdown of what happened....
Let me know if I'm off base or have other pertinent info.
There was some action in NE Iraq where a American contractor was killed.
In retaliation we attacked some targets in NE Iran to destroy the bases the previous attack originated from.
Then the Iranians attacked the American embassy in IRAQ. This attack was with Iranian operatives directed by Quds leader Soleimani. Ayatollah Ali Khamenei says there's nothing Trump can do about it. Trump orders a successful drone attack on him at the Bagdad airport.
Ayatollah Ali Khamenei promises revenge.