First, this is completely untrue. Hamas and Hezbollah have been launching missiles at Israel literally nonstop for 20 years. The houithis have and will continue to launch missiles at US assets along the Bab al-Mandab Strait. All of these missiles came directly from the iranian regime. Those groups are an arm of the Iranian government
Thats not the point though. There is no reason for either party to respond proportionally in a war. Going to war against an equal weight class as idiocy, sun tzu figured that one out forever ago.