Could back-channel diplomacy prevent a Middle East war?

Everyone in the US, from President Biden to Bill Burns, the CIA director, to Antony Blinken, the secretary of state, are working overtime this weekend to persuade/deter/prevent Iran from launching an all-out war against Israel, alongside Hezbollah, Hamas, and the Houthis in Yemen. Previously when Iran has threatened war with Israel, the US had been reasonably sure that Tehran really didn't want outright conflict but preferred rather to use its proxies to attack the Israelis. Then on April 13, Iran launched a huge drone and missile barrage on Israel in retaliation for the Israeli airstrike on an Iranian consulate building in Damascus. It was the first time Iran had directly attacked Israel and although the majority of the ballistic missiles and drones were shot down by Israeli air defences, it set a dangerous precedent. So the chances of Iran launching another attack directly on Israel are very high after the assassination of the Hamas political leader in Tehran. Can Washington persuade Tehran to hold fire? I seriously doubt it which is why the Pentagon has moved an aircraft carrir and dozens of fighter jets to the Middle East in preparation for a crisis. The attack from Iran could come this week. The world awaits.