Depends on the protester and what they are protesting but many of Israel protests have been against US continuing to support/fund Israel and want US government to do something different.
Iran on other hand is US sanctioned and US actively works against it, very different relationship then with Israel.
When Israel does this to Palestinians with US made planes and US made bombs, bought largely by US tax dollars? Over and over again for more than 2 years? Shielded from consequences in the UN by the US? Seems pretty sus that Americans would protest that in particular.
I demand for Israel the same sanctions that they are applying to Iran and Russia. Are you happy now?
As the comment you just replied to says, Iran is already sanctioned and bombed, while Israel gets billions in military (and other) aid from US and the rest of the West. It's abundantly clear that there's a difference.
And furthermore, so you have to have a decibel meter perfectly calibrated for every tragedy that happens on planet earth, or your arguments are nullified? Preposterous.