It doesn't change the fact that Israel is a member of the UN as Cipora so aptly pointed out, and yes, it is useless in the respect that despite all its resolutions, Israel does what it wants anyway without any censure for its actions, of course with US vetoes usually. I think you meant that America gets bad-mouthed for Israeli support and not the other way round, which is understandible. How can America maintain any credibility when it tries to represent itself to be the great defender of human rights and democracy, and then it gives its unconditional support to a country who tramples over an entire people.
Police disperse hundreds in brawl in Kafr Manda, northern Israel (Haaretz)
from the article: Barak's mail to Yale