If Israel and Iran were to go to war, how will it play out? Who will be on each side? How do the weapons compare?
It would be ugly and fast as Iran’s primary and really only way to decimate Israel is via ballistic missile strikes.
Iran and its proxies launch volleys of several hundred rocket artillery and TBM missiles at Israel at a time. Israel’s missile defenses would be overwhelmed, even if they intercept with a 90%+ probability, simply put there wouldn’t be enough ABMs ready to intercept over a critical time window.
Depending on how damaged Israel’s airports are or if it was able to get most its jets off the ground, it would launch a mega air campaign.;
Provided Israel can continue its air campaign and has operational airports or other roads it can use, it may continue conventional warfare and attack Iranian missile launch sites and other targets from the air. It should have no trouble taking out the Iranian airforce. Neutralizing air defenses would take longer.
However, given how small Israel is, there is a high probability that it would simply not be able to justify and tolerate the kind of damage and death toll a TBM ballistic missile onslaught could deliver. Its airports could also be rendered inoperable after the first few rounds of missile strikes and it would not be able to wage a proper air campaign. In such an event, without any doubt, Israel would hit Iran with an array of Jericho II/III IRBM/ICBM ballistic missiles as well as submarine-launched nuclear-armed cruise missiles, delivering tens of tactical nuclear strikes (50kt – 300kt each) across key targets. This is the primary deterrent Israel has against Iran choosing to shower it with ballistic missiles and why it can never allow Iran to develop a nuclear weapon. That being said, the U.S would hit Iran at full conventional might just as well and especially if Israel is put in a position where it has to resort to using nuclear weapons.
This war would have a high probability of turning out to be incredibly ugly and catastrophic for the region and planet. All would depend on how well and fast Israel and U.S would be able to neutralize Iran’s ballistic missile arsenal.
Update: A lot has happened over 2020 and once again Israeli SEAD platforms have been used in conflict, this time in the Nagorno-Karabakh War, while having already proven themselves against Russian made point defenses such as the Pantsir S1 in Syria, this time the Israeli IAI Harop II was used to take out the much lauded S-300, destroying up to three or more S-300 batteries comprised of various modules. This is very relevant to the topic at hand, because Iran’s best and most prized air defense system is the S-300. some footage of this action has been released and can be found below:
View from above S-300 launcher
View from back of S-300 launch truck