Point being, Iran wants us dead. Not funny.
More than half of the world, including Russia, wants you dead. It's not because they hate who you are, your culture, language, civilisation, etc... They hate you for what are you doing (basically you are killing them, interfering with their inner politics, robbering them, commiting numerous acts of unprovoked and illegal aggressions, supporting international terrorism and so on).
And if you don't do something extremely provocative, most of you can peacefully coexist with them. Absolute majority of Americans are nice people. The problem is with your ruling regime (which is, quite possible, isn't actually "your", but it is definitely up to you to decide).
Ok, Obama and Hillary thought getting rid of Qadaffi was a good thing (it was) and made it happen. Trump thinks getting rid of Iran's nuclear and missile programs are a good thing (it is) and is making it happen.
And both of them were wrong. I don't know for whom it was good, but it was definitely bad both for America and Africa/Middle East. As a rational thinking person I prefer to think, that there is may be evil, but rationally thinking, backroom group, who actually, some way, benefited from all this mess. But, may be, it's just my wishful-thinking and there is no evil wizards somewhere behind the scene, just stupidity and incompetence of real decision-makers.
The "root cause" of the Gaza mess is Hamas, and the root cause of Hamas is Iran. Without Iran Hamas and Hezbollah are much less problematic.
Actually, it was Israel's actions that raised both Hamas and Hezbollah.
We get involved when vicious dictators' regimes get too threatening, Qadaffi, Saddam, Kohmeini, all gone. There is no "victory" just peaceful coexistence with us and Israel. If Iran got nukes and ICBMs it would not be a pissant fight, but very serious business.
If you destroyed the previous world order, you shouldn't be surprised that all players are going to regime "might is right". And nuclear Iran is much lesser problem (for America) than nuclear Brazil, nuclear Mexico or nuclear Cuba.
The enemy of your enemy is your next problem. They will turn on you instantly. It happened many times in history, even in the modern American history.