What context of the Zionist project justifies Hamas' actions and intent? ... they both "suck".

Colonizing might not be the right word to use for Zionism. It was used historically. But the more appropriate word in today's time might be "asylum seeking". The Holocaust was not the primary motivation for Israel (as you mentioned), nor was it capitalistic settler-colonialism that is referenced in contemporary understanding. It was to escape persecution - "pogroms" and the like.

This is an understandable reason to seek refuge. Many debated coming to the US instead of forming Israel. But there was reasonable fear that Jews would face the same oppression there.. which is understandable given the US's racist past. Turns out, folks that went to the US made the right choice. But this wasn't so clear at the time.

"Palestine" was not a state when Zionism began. There was no "Palestinian people". There was a diverse group of Arab people living in a territory controlled by the Ottoman Empire. This territory happened to also be the ancestral homelands of Jewish people. Jews emigrated to this land to join other native (though much less populous) Jews in the area.