Israel's attack wasn't entirely unprovoked; Iran frequently calls for attacks on Israel, wiping them from the face of the earth, and funding organizations that attack Israel. The fear that they might use nuclear weapons offensively against Israel is very real.

Note that I'm not a fan of Israel, condemn their genocide in Gaza, and consider Netanyahu a war criminal. I'm also not a fan of this attack on Iran and prefer a peaceful and democratic overthrow of that regime. But calling the attack unprovoked is not entirely correct; Iran spends a lot of time provoking Israel.