The US–Iran deal has a hole shaped like Lebanon. Iran insists any agreement must also end the fighting there, and a Hezbollah politician said he was confident Iran was negotiating "including the file of Lebanon." [E1] But Israel isn't a party to the deal, and says it'll keep striking and won't leave the Lebanese ground it holds. Two sides with opposite demands for the same agreement — and one of them isn't in the room.
The shooting hasn't slowed for the talks. Israeli airstrikes killed 13 people in south Lebanon on 10 June, part of a campaign Lebanese authorities say has killed nearly 3,700 since early March. [E2] Lebanon's defence ministry counted 3,491 Israeli airstrikes between 17 April and 7 June — during what's nominally a ceasefire. [E3] A deal that reopens Hormuz but leaves this running hasn't ended the war. It's just moved it.
So Lebanon is the likeliest place a signature slips. The logic is simple: Iran and Hezbollah think Lebanon is inside the deal, Israel thinks it's outside and is acting like it, and one fresh strike or rocket gives either side a reason to walk. If the weekend's optimism cracks, watch this seam first.