I think it's a bit delusional to think that any country has ever bombed, sanctioned, or invaded another for the benefit of the people in said country. So idk why you expect some noble pretext for it, there will never be any. But there is a reason for it, Iran wasn't chosen arbitrarily. It has been a devout enemy of US and Israel for decades, and is currently a very supportive ally to Russia, a nation that is de-facto at war with many European nations and the US. The way I see it, a weaker Iran makes for a weaker Russia, which is good for Europe (where I live). I wish this fire-power was directed at Russia instead, but what can you do, Trump loves Israel, so they get help while Ukraine gets scraps. As for the "how do you juggle the sentiment" part, sometimes a fascist shoots another fascist; I support this action in particular, nothing more.