Yes, the killing of General Suleimani by the US Trump administration in January 2020 damaged the Iranian coalition badly. His replacemant Gen. Qaani was not as good. Despite the surprise (Hamas did not inform Iran of the attack) had Suleimani been still alive and kicking he would have orderdd Hezbollah to fully attack Israel at its worst moment since its inception inj 1948. A ground attack from the north and south plus a combined attack with 3-4 hundred Iranian missile and scores of Iraqi missiles and drones could have caused unimaginable damage. The Galilee could have been conquered. Countless Israeli dead citizens. Total havoc. Israel would have survived, but the damage and decline... And Iran would have been unscathed and better off than ever.