The United Nations said on Saturday the Gaza war was “staining humanity” on the eve of its 100th day as Israeli Prime Minister Benjamin Netanyahu doubled down on vows to defeat Hamas. The conflict has unleashed a devastating humanitarian crisis in the Gaza Strip, and fears of a regional escalation intensified after US and British forces struck pro-Hamas Houthi rebels in Yemen on Friday following attacks on Red Sea shipping. The war started on October 7, the day Hamas launched a surprise attack on southern Israel, in response to decades of blockade, aggression and occupation, the group says, re…