A lot of group think going on here as per usual.
You won't find a better article on the topic than this one: https://www.google.com.au/amp/s/amp.cnn.com/cnn/2016/12/26/opinions/us-role-in-israel-un-vote-was-hypocritical-goldfeder/index.html
A better article?
Ok, for starters, its an opinion piece. Which is fine. But he treats the opinion of , for instance, Kontorovich that the Mandate continues under international law to grant legal ownership of the land as unassailable. When in fact it's not. There is much dissenting from this view in international law circles.
But even if true, Israel is being incredibly disingenuous and selective. The Golan Heights were never within the British Mandate. They fell inside French territory and therefore became Syrian. The capture of this area cannot be claimed as re-taking but were instead an outright conquest and annexation. As such, the settlement program in this zone, to my mind, absolutely contravenes the 4th Geneva provisions and whilst i totally support the right of Israel to exist, i find it troubling that Jews are looking for technical ways around Geneva Acords.
As to East Jerusalem, personally i fail to see how Israel didnt undermine its own legal claim re the Mandate by formally agreeing to split the city with Jordan in 1948. Note that the UN had declared Jerusalem an International city to be held by neither party and that both warring nations had to fight their way to it and then negotiate a deal. Which I'd have thought then made the seizure of it in 1967 an armed conquest and once again brings it under the Geneva rules. But of course, im not a lawyer. Either way Israel simply rejects that it applies and instead arbitrarily decides which parts to abide by and which parts to ignore. Again, that bothers me. Then we have Netanyahu declaring that "the western wall isnt an occupation". Except that its not just the Wall. Its also suburbs that sprawl well to the North and East and now encompass some pretty draconian residency requirements on Arabs not to lose their rights to even dwell there (Rights that should be protected by the Mandate if one is to continue to afford it any credibility on the other matters it is being used to justify.)
As to the first part of the article, an entirely personal and poorly built (imo) ramble, the thing that stood out most to me was this:
"who waited until there was absolutely zero political accountability before reversing his previously held position on vetoing anti-Israel Security Council resolutions".
You could easily suggest from this that its actually only "political accountability " that keeps the US position. Which raises the obvious question as to whether its actually "right" in any moral sense.
Im far far from an 'expert' but i think perhaps the above sums up the problems all round. Its an ugly mess of quasi legal, political and religious bigotry from all parties and humanity too easily forgotten.