This has happened over and over again.
Per Richard Armitage of the "We will bomb you the stone age..." fame, he was pleasantly surprised how easy Gen Musharraf agreed to US demands vis a vis Afghanistan post 9/11.
Gen Zinni was sitting in Rawalpindi when US launched Tomahawks to get OBL back when Clinton was trying to deflect from his impeachment. He told our establishment that Tomahawks are inbound 5 minutes before they entered Pak air space and to stand down and don't mistake it as a launch from India.
Similarly here, BaghlolCo already had a plan ready, they just used the displeasure of a 3rd tier State Dept employee as "Hukum from sirkar" or casus belli to initiate regime Change. Initially US might have been pleasantly surprised (again) of getting rid of IK for a very small price but now blowback has them rethinking.