There is no going back to the days before October 7, 2023 - before Hamas stormed across Israel's borders to murder, rape, maim and kidnap innocent civilians.
Now, there's no going back to a time before April 13, 2024, either.
The world irrevocably changed on Saturday when Iran's Supreme Leader Ayatollah Ali Khamenei unleashed, for the first time, a direct attack on the Jewish State from Iranian territory.
Israel has now proven, in the most significant way yet, the superiority of its missile defensive systems by intercepting over 95 percent of the hundreds of armed drones, cruise missiles and ballistic missiles launched by Tehran.
However, pride in this technological wizardry mustn't lull Israel or its allies into a false sense of security or diminish the severity of this change in the Middle East's savage rules of engagement.
Make no mistake – the threat to Israel's existence is greater today than it has ever been before.
For decades, Tehran has acted as the head of a terrorist octopus, lashing out at its Western foes with long tentacles in the form of proxy armies arrayed in a ring of fire around Israel (Hamas and Islamic Jihad in Gaza, Hezbollah in Lebanon, and militias in Yemen, Syria and Iraq).
But these new attacks raise the stakes dramatically.
Iran's assault came in response to an Israeli Air Force strike in Damascus earlier this month, which killed Mohammad Reza Zahedi the commander of the Islamic Revolutionary Guard Corps-Quds Force in Syria and Lebanon.
Zahedi was a big fish. He was responsible for numerous terrorist attacks on Israel and participated in an Iranian-backed militia attack that killed three American troops in Jordan in January.
There is also evidence that he participated in the planning and execution of the October 7 attacks - and at the time of his assassination, Zahedi was planning other terror plots.
Israel was acting well within the rules of its dangerous neighborhood by taking him out. But the Ayatollah responded with a potentially catastrophic barrage on Israeli civilians, military bases and government facilities.
If Iran walks away from this moment without paying a severe price, Tehran may be emboldened to deploy its weapons again. And the next time, these drones and missiles may be armed with nuclear or chemical payloads.
Yet today, some are arguing that Israel's response must match the actual damage, not the potential devastation, caused by the Iranian attack.
Only a few of Iran's deadly drones and missiles actually penetrated the Israeli 'Iron Curtain' of incredible air defenses, and those that did scarcely caused significant damage or causalities, save for the serious injury of a seven-year-old Israeli Bedouin girl who remains in hospital.
'You got a win. Take the win,' President Biden reportedly advised Israel Prime Minister Benjamin Netanyahu, while warning the U.S. would not support an Israeli counterattack on Iran.
It would be a mistake for Israel to heed Biden's advice.
The concept of 'deterrence by denial', where Israel uses its military and technology to limit the cost of attacks on its civilians, is a fatally flawed strategy.
Indeed, 'deterrence by denial' failed spectacularly on October 7, when Israel failed to foresee and foil the attack from Hamas.
Israel must now adopt a doctrine of 'deterrence by punishment' where it inflicts disproportionate costs on its enemies and focuses its response on a few priority targets.
The Israeli military could destroy the weapons deployed against them, including unnamed aerial vehicle development and production plants, as well as cruise missile and drone storage facilities inside Iran.
Israel could also hit Iranian ports, oil and gas refineries, pipelines, and other infrastructure that finance the regime.
Other targets could include leadership assets. Such strikes have the added deterrent effect of demonstrating the long arm of Israel's intelligence and military capabilities.
But the Israeli military's most important strategic target should be Iran's nuclear weapons program.
Israeli attention, which in recent decades has focused on delaying Tehran's progress in fissile material production, must now shift to neutralizing Iran's nuclear scientists and their ability to build an actual weapon.
Right now, Tehran is building a new heavily fortified facility near Natanz in central Iran that is reportedly designed to extend over 100 meters underground and is buried under a mountain.
It is here that Iran could develop an enrichment plant powered by advanced centrifuges capable of producing multiple nuclear weapons without detection.
If completed, the Natanz facility could be impervious to Israeli and even American bombs.
Though, in contrast to Israeli 'deterrence by punishment', President Biden will dangle new weapons sales, political support and continued intelligence and defensive cooperation in front of Netanyahu in exchange for quiet in the Middle East before the November elections.
Biden's thinking right now is short-term.
His political advisers don't want to risk a widening conflict threatening the flow of oil supplies and causing domestic gas prices to rise, or making Biden appear to be a feckless observer to an international crisis.
Israel must think long-term.
Biden's supposedly steadfast support for Israel after October 7 has diminished as he faced political pressure from the extreme left of his party. There's no reason Biden's will won't weaken again.
Israel's enemies will also interpret the lack of any meaningful response as weakness and capitulation to American demands. This will immediately influence their behavior in Gaza, Lebanon, and the West Bank, and reduce the chances that Hamas releases its hostages.
After this weekend, the threat of a nuclear weapon being deployed from inside Iran toward Israel is a step closer to reality.
Israel must decide for itself the nature and timing of its response, but it must inflict serious damage on Iranian Supreme Leader Ali Khamenei and his regime to restore Israeli deterrence.
Brig. Gen. (res.) Jacob Nagel is a senior fellow at the Foundation for Defense of Democracies (FDD) and a professor at the Technion. He served as National Security Advisor to Prime Minister Netanyahu and as acting head of the National Security Council. Mark Dubowitz is FDD's chief executive and an expert on Iran's nuclear program and sanctions. In 2019, he was sanctioned by Iran.