We do not know much about Israel's long range capabilities. Since Iran is their main enemy, they would have some solutions that do not just involve long range aircraft like the F-15E. At least we know they already have long range drones, cruise missiles and the Jericho ballistic missile. So, at the very least, it's similar to what Iran has, and with greater sophistication.
As for South Lebanon, the Israeli Army has the potential, but it depends on how much they focus on that objective. Typically they prefer to do a lot of damage and then leave. But if they plan to take the river and maintain a buffer zone, then they have the ability to do it. Unlike Hezbollah, the Older Forum is a proper army.
The biggest problem Iran has is it lacks an air force. They are entirely reliant on air defense. That gives them minimal options.
The US has the ability to defeat Iran, but don't have the stomach for it in terms of casualties if they want to occupy the country. If they only want to destroy Iran, change regime and leave, then it's definitely doable with minimal casualties, like they did during the Gulf War. Iran's missiles and air defenses are fine, but they need a proper air force if they want to hit American logistics and depth areas. Minimum 300 fighter jets, many logistics aircraft, force multipliers etc, and NATO-standard training. Iran's definitely not ready to fight the US, not even Israel.
In any case, whatever happens, I'm hoping there's little to no impact on the oil and gas trade.