That is because allowing the provision to expire would remove Iran’s nuclear program from the Security Council’s agenda, effectively declaring that there are no international concerns about its potential military uses. So assuming the snapback happens, UN member states will once more be under the obligation to enforce sanctions, including an arms embargo, on Iran. Instead, snapback sanctions threaten to take us into further sterile confrontation. Unlike in 2015, these talks would have to address, in some form, Iran’s regional behaviour and involve regional players. Rob Macaire is a member of the Atlantic Council’s Iran Strategy Project advisory committee and a former British ambassador to Iran.