OP said he didn't read the whole thing. Your statement about the Nazis is historically incorrect. It was first in 1941 that the Nazis settled on "the final solution." They were 8 years before extermination became their goal. Prior to that the Nazis just wanted the Jews gone, not necessarily dead.
Your final statement is both a clear war crime and genocide. The Geneva convention is clear: There is no justification for genocide. It does not matter how horrific Hamas is (and they have been definitely horrific). Hamas' actions do not justify Israel committing war crimes and genocide. It is very simple.
Making it even more simple: Gaza is occupied territory. Israel is committing war crimes by firing into and attacking into Gaza.