I think what needs to happen is that Israel has to be sanctioned by the UN. If China starts doing unilateral sanctions then it's no different from what the US is doing. Even if sanctions are done for the right reasons, it's still the wrong approach. We need to actually use the UN to reach consensus among different nations, then act upon that basis. While the security council does have vetos, the general assembly does not, and that's where measures against Israel can be passed.