Caveat: Many people don't know they're part of this because they're simply listening to the talking heads they trust.
Essentially, there is a Christian cult and it's goal requires Israel. Israel, of course, wants to continue to exist. As do Jewish people. So of course, they're going to work hand in glove. The people who are against "Christ is king"? The people who want to keep forcing the point that "The Jewish were and still are god's chosen people"?
It all stems from the cult of the red heifer. It is the belief among some Christians that the Jewish temple in Israel must be rebuilt before the end of the world can happen. That if Israel falls. That if Jewish people are scattered beyond recovery. If those things happen? God will abandon us and our proper end will never happen.
The Jewish people who are part of this cult of the red heifer, they believe that the final temple will result in the true messiah appearing on earth.
3 conditions must be satisfied.
1.) An unblemished, never worked, perfectly red furred cow must be born and ritualistically sacrificed.
2.) The ashes must be used on workers, so that the final temple of Israel can be rebuilt.
3.) The completed temple must then host the most sacred forms of worship. The messiah/end times can then come.
So you have Christians who are convinced they need the Jewish people to bring about eternal peace and happiness on earth. You have Jews that just want to be benefactors of this in the form of protection, support, etc, and then you have the jews who believe that it'll result in the true messiah.
These people are VERY prevalent among the NeoCon conservatives and bluedog democrats. This is also, not surprisingly, why they fear populists so much. On both sides. Populists aren't going to defend Israel.
So there you go. That's why some of our Christian NeoCons are so balls deep and all in for Israel. And because waiting for a red cow is so fucking absurd, and being part of "I want the world to end in my lifetime" cults is weird, they'll never admit to this.
It's not obscure. OP is actually making it sound weirder by highlighting specific requirements of one "flavor" of the prophecy. It's actually a common belief of evangelicals and Mormons alike. Everyone I know understands at least some of this, like the requirement of the temple being rebuilt. I'm not knowledgeable on scripture but it's supposedly biblically based in Revelation. Christians and Jews have different perspectives on the prophetical points. Jews think the messiah will come while Christians know it as the antichrist. Christians don't actually care about the red heifer but they're perfectly willing to let Jews go through the motions and see what happens. Most Christians would say you can't trick God and it's wrong to try and force prophecy, but if certain coincidences start lining up they aren't going to say it's NOT prophecy coming true.
Still, it would be wrong to blame American Christians as the ones driving unconditional support of Israel. Politicians would do that anyway because they're bought and paid. What the belief allowed was the coopting of American conservatives by the deep state of Israel, since religious people look the other way when they hear news about Israel spies, or undue amounts of money being sent there - rather than complain to their congressman like they might otherwise.
It might be more accurate to say that Christian end-times thinking is part of what allowed the creation of Israel in the first place via Great Britain partitioning the region.