The question should make you uncomfortable because of the answer you're trying very hard to dance around. It doesn't make that answer any less valid.
To respond to your points:
1) No one is demanding unquestioning support to Israel. I abhor a lot of what Israel does and I suspect and hope that part of the eventual peace process will include Netenyahu being charged and punished.
2) This is just a facet of point 1 and one that isn't really valid. It's almost universal among American Jews that they'll qualify "I don't support the Israeli government" when discussing this topic. It's at the point where it's frankly insulting to have to constantly reassure whoever I'm talking to that I'm not a monster who supports the settlers or the other abhorrent actions of Likud and Netenyahu.
3) This is again basically just point 1 restated, and it still doesn't make sense. Israel is constantly accused of genocide, carpet bombing, and ethnic cleansing. If they were actually doing any of those things in Gaza, I'd condemn them for it. You can make the case they're doing ethnic cleansing in the West Bank (albeit very slowly), and I do condemn them for that. So... how is this point valid at all?
4) Emotional blackmail? What are you talking about? Guilt over the holocaust?
The entity in this conflict that insists they're innocent victims and must have the unwavering support (and lots and lots of money that they use for war and give nothing back) is not Israel. This is top tier gaslighting honestly.
The US gives Israel military funding that they must use to purchase weapons and equipment from American companies. It's a US stimulus package with extra steps.
Israel contributes immeasurable technology and culture to the world. They've been increasing the amount of habitable land, food produced, water available, and the quality of life in that region since before Israel was a state.
Hamas takes aid and uses it to make war.
In terms of just objective viewing of our foreign policy around the world:
Israel, for all its problems, is a demonstrably freer society that better represents Western values than many if not most of our global allies.
We work with the Saudi's for geopolitical gain but we don't particularly like them. We prefer them to Iran so they get a pass on dismembering US journalists or flying planes into our buildings.
We work with Assad in Syria if we have a common enemy like ISIS. Assad actually committed genocide, unlike the Israelis. Bonus points for chemical weapons.
We work with Sweden and they secretly sterilized 60,000 Romani women they didn't think were genetically pure enough. They still discriminate against the Sami along with the rest of the Scandinavian countries. No one on the left seems to have any issue with any of it, if they even know it's going on.
Pakistan, our alleged ally that harbored Osama Bin Laden, announced this week they're expelling 1.4 million Afghanis, many of whom have been in the country since the 70's. That very clear ethnic cleansing is I guess... fine? There certainly haven't been any protests on college campuses I'm aware of.
I can keep going. Again, it's ONLY Israel that inspires this passionate response from the left. ONLY Israel that merits wall to wall news coverage for what is a pretty small conflict if you put it next to the 400,000 dead in Yemen (so far), 500,000-600,000 dead in the Syrian civil war (so far), Iran ramping up executions, etc etc etc.
You haven't really given a clear answer, but you've at least acknowledged the question so that's progress.