“One of the reasons Israel has tried to avoid a two-front war, going against Hezbollah and Hamas at the same time, is because it can’t afford to have both Tamar and Leviathan shut down at the same time,” he said. “It doesn’t have an alternative to the gas. But if you hit those fields, you’re hurting your friends, not just your enemies — so this cooperation is also something of a source of deterrence.”