"Russia invaded Ukraine." Big country with huge military invaded a small country with a small military. There's two organized armies fighting each other but one is a smol bean who the USA must help out.
"Israel invaded the Palestinian territories." Israel has a standing military with mandatory service, the Palestinians aren't supposed to be able to have an organized military force to match it. After a successful series of raids by a few thousand members of an organized military force the Israel military has spend the last few months obliterating civilians, civilian infrastructure, and all the places that are supposed to be immune to intentional targeting (schools, hospitals, sources of water, sewage treatment, religious places, evacuation corridors, etc). So if the USA'ians are supposed to support the underdog... like as is the case with Ukraine... it makes it hard to support Israel.
The basic optics are:
"Russia invaded Ukraine." Big country with huge military invaded a small country with a small military. There's two organized armies fighting each other but one is a smol bean who the USA must help out.
"Israel invaded the Palestinian territories." Israel has a standing military with mandatory service, the Palestinians aren't supposed to be able to have an organized military force to match it. After a successful series of raids by a few thousand members of an organized military force the Israel military has spend the last few months obliterating civilians, civilian infrastructure, and all the places that are supposed to be immune to intentional targeting (schools, hospitals, sources of water, sewage treatment, religious places, evacuation corridors, etc). So if the USA'ians are supposed to support the underdog... like as is the case with Ukraine... it makes it hard to support Israel.