It would be the only concrete proof for them that their religion isn’t a lie.

Evangelicals have an entire grab-bag of faith healing and "I saw Angels in my oatmeal" testimonials and apocryphal accounts of magic golden tablets that you can only read inside a man's hat. FFS, there's an entire Ark Adventure exhibit in Kentucky. Nevermind the crushing volume of religious artifacts and icons and reliquaries scattered all through Europe, North Africa, and the Middle East. No shortage of things religious people can point to as "proof" enough to satisfy themselves.

Modern Millenarianism isn't just proof, it's vindication. It's a final triumphant Fuck You to the heretics, as you're wisked off into the box seats at the right hand of the Correct Kind Of Jesus to point and laugh at all the infidels who didn't do the correct religion correctly.

If I was Israeli I don’t think I’d be comfortable with the “support” I get from Evangelical Christians.

Zionists have their own spin on things, wherein they're proven right and all the goys get humiliated. In their version, the Israelis rule humanity for a thousand years from a Utopian Kingdom occupied by the Correct Jews. And then God showers them with blessings so long as they do the correct number of animal sacrifices on the correctly sanctified big stone table in the correct big stone building using the correct magic words.

Everyone's thinking they've got the magic beans and the other person is being stuck with the dried up milk cow. That's what keeps the engine turning.