A second Iranian attack on Israel would likely dwarf its first

• Iran may conclude it needs to strike Israel with a larger salvo than it did in April.
• Iran and its allies are seeking retaliation after two killings as the risk of a regional war grows.
• "If Iran wants to maintain deterrence, it has to scale up its responses," an expert said.

Iran has repeatedly vowed it will attack Israel in response to the assassination of Hamas' political leader in Tehran on July 31. Its main proxy, Hezbollah in Lebanon, has also vowed to join Iran to avenge Israel's killing of one of its most senior commanders, Fuad Shukr, in Beirut the day before.