Sure, I would agree with what you just said. The meme though, said that no behavior justifies bombing another country, as that's their problem to figure out. But obviously that's flawed.
I'm not justifying any particular war or action. Especially these most recent ones. Just pushing back against overly black-and-white thinking. Every action should be judged based on its merits.
Would it be a defensive war? The only action taken against Iran in the past while was the bombing of their nuclear facilities, which was clearly a US action. Israel cheered it on, sure, but what action had Israel taken against Iran that would have justified Iran bombing them?
Iran isn't Palestine. Iran isn't Lebanon (despite all of their proxy militants there). I'm not justifying any of Israel's actions, but Iran bombing them would be more like if Poland started lobbing bombs at Russia, which I think we all agree would be a big escalation.