You obviously do not understand US democracy. Congress passes laws, but its domain is limited and it relies on the Executive to enforce them. Congress cannot dictate how the President deals with foreign countries. Both houses could pass resolutions demanding a certain vote at the UN and Obama would be perfectly free to disregard it. Obama cannot give foreign aid without Congress approving the funding, but he does not have to release foreign aid allocated by Congress. Congress has very little ability to interfere with a rational Israeli policy. If Obama wants to cut off aid to Israel and vote against it in the UN, Congress can do nothing about it. Moreover, "support of Israel" does not necessarily mean support of the settlements and occupation. The recent Congressional letter re Israel said nothing about these issues. The vast majority of Americans support Israel's existence, but far fewer support its WB and Gaza policies.
Protests in southern Syrian city after Druze cleric's death (AP)
from the article: Netanyahu and Obama are at point of no return