The General Assembly can't take any action. That power is reserved for the Security Council which neither is controlled by a single nation as 14/15 countries vote against the US.
The only thing the condemning states can do is assist the state failing to support it's population, which in this case is Palestine. If that can't happen, states should take collective action to protect the populace. They are however hindered by Israel and the Security Council is the only one who can decide for military intervention ¯\(--)_/¯
So no, my reply is not logically shaky. It accurately points out that there isn't a single state controlling the UN.