You miss the point, In the event of a nuclear war, Israel's enemies would turn into dust, how could you invade Israel, if your country was nuked? Or your army? Israel has nuclear armed submarines right next to Iran, you wouldn't be able to fire more than a few missiles until Tehran would burn.
Talking about invading Israel, trough who will you invade Israel? Do you actually think you can supply and maintain logistics for millions of soldiers, far away from your own country and infrastructure? and do you think we will fight a war of attrition with you, even if you somehow will be able to field your troops nearby Israel?
Israel is stronger than Iran conventionally and unconventionally.
Again, HOW CAN YOU COUNTERMEASURE AFTER YOU ARE DEAD?
You're not being realistic.
Israel will never fight a nuclear war against Iran because it will backfire badly on Israel's own existence/survival.
First of all, no Muslim power will allow Israel to nuke Iran. You might as well forget about garnering such support. Even if Israel gets the tacit approval of the pathetic Gulf states for a nuclear attack on Iran, which I highly doubt will ever occur since not even the Gulf states can stoop this low, you can bet your bottom dollar that major Muslim military powers such as Turkey, Egypt and Pakistan will be vehemently against it.
An Israeli nuclear attack on Iran will alarm the entire Muslim World. The leaders and citizens of Turkey, Egypt, Pakistan, Indonesia and many other Muslim-majority countries will fear that it will set a bad precedent for the Israeli army and other non-Muslim armies to use nuclear weapons or other kinds of weapons of mass destruction in future conflicts between Muslim states and non-Muslim states. The vast majority of Muslims outside Iran will assume that Israel will not hesitate using nukes against them as well in future conflicts, therefore this kind of lunacy will simply initiate a huge nuclear arms race that will lead to nuclear proliferation across the entire Muslim World. Countries such as Egypt, Turkey, Indonesia and even the Gulf states will begin to pursue nuclear weapons in order to deter Israel from ever attacking them in the unforeseeable future.
Simply put, an Israeli nuclear attack on Iran is against the geopolitical and economic interests of all Muslim-majority states, including the Gulf states that are passionately anti-Iranian. In fact, this kind of an attack will lead to another global economic recession, so in reality it doesn't benefit anyone around the world. No one will allow the situation to go that far, not even Donald Trump. And should Donald Trump ever go that far, you can rest assured that he will be assassinated by his own intelligence agencies. There are many limits and red lines in politics. The Americans aren't going to risk starting a mutually destructive thermonuclear world war for the sake of teeny-weeny Israel. There's no telling how nuclear-armed global powers such as Russia and China would react if Israel ever dares to cross the boundaries of international law and diplomacy.
Another consequence of an Israeli nuclear attack on Iran is a very likely regional military response by nearby Muslim countries. Turkey will not sit idly by and watch Iran get destroyed by Israeli nukes. Any kind of societal collapse in Iran will inevitably spill over into Turkey and undermine that country's territorial integrity. The Turks will take it upon themselves to intervene against Israel in one form or another, either by directly attacking a limited number of targets in Israel in order to neutralize the Israeli air force or by quietly arming the Iranian military with NATO weapons in order to give it the ability to strike back at Israel. Speaking of which, even Pakistan might quietly/secretly give a couple of nuclear warheads to the Iranians in this kind of situation.
In short, don't expect a quiet Muslim World if Iran gets attacked. The Sunni versus Shia cold war will end abruptly if Israel uses nukes against any Muslim country, Iran or otherwise. Many geopolitical calculations will change dramatically and spontaneously, and countries that were once friendly with Israel might suddenly change their stance. Israel will foolishly create an environment of unpredictability that will put the country at a greater risk of being wiped out.
So many opportunistic groups will take advantage of the situation to morally justify a war on Israel. Arab nationalists will use it as a golden opportunity to increase the funding and arming of Palestinian nationalist movements. Islamist groups aligned with Turkey and Iran will use the situation as a golden opportunity to increase their attacks on Israel. Even Israel's Western friends will be locally and externally pressured to move away from Israel in order to prevent the situation from getting worse and escalating into a global war. Israel's actions will run contrary to internationally-accepted rules of engagement. The consequences of this kind of decision will be far-reaching and dire for the Israelis.
Hopefully you now realize how unrealistic your argument was.
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As I've said before, Israel can win against Iran in two ways:
1. It can continue to covertly fight a proxy war against the Iranians by quietly supporting anti-Iranian groups both inside and outside Iran. For example, it can quietly support Kurdish and Balochi separatists in Iran, and it can also support the Iraqi and Syrian Kurds in order to use them as a counterweight against Iranian expansionism in the Fertile Crescent.
2. In the worst possible case, it can fight a very limited conventional war against Iran in order to swiftly achieve a number of short-term military objectives. This kind of confrontation will likely take place somewhere near the Golan Heights, and it is contingent on Iran carrying out the first attack. In this case, Israel can respond to a hypothetical Iranian attack on the Golan Heights by successfully neutralizing the Iranian threat near its borders. In this kind of conventional military confrontation, Israel will naturally have the upper hand by virtue of its superior military technology. Israeli jets will without a doubt fare better against Iranian jets, and Israeli tanks will no doubt be more effective than their Iranian counterparts. Having said that, the likelihood of a limited conventional war initiated by Iran is very, very slim. Iran knows its military is technologically weaker, therefore it's not stupid enough to fight conventionally against Israel. Iran will most likely fight an asymmetric/irregular war, which is what it's best at. But should Iran ever start a conventional war against Israel, then Israel can definitely win due to its technological superiority.
Apart from these two scenarios, there's no other way Israel can win. Israel cannot win by resorting to an excessive show of force as that would border on becoming an unconventional war. Anything excessive and non-conventional will bring about a very harsh, irregular/asymmetric response from Iran.
You have to be pragmatic.
Both Iran and Israel are capable of achieving victory against each other, but it will all depend on how the war is fought.