It was the idea of Christian-Zionism being planted into the Evangelical churches; these idea spread to all denominations eventually.
The Schofield Bible, with commentary, made back in the early 1900's (from Oxford) planted the idea that those who bless Israel will be blessed and those how cursed Israel will be cursed.
It also implanted the idea that God had given the land of Israel to the seed of Abraham.
All of these commentaries have no basis, but were widely promoted through Christian colleges and universities, along with a steady dose of 'prophecy fulfillment' regarding the return of the Jews to Palestine and an endtime apocalyptic scenario.
The 'return of Jesus' also plays well with most people who have no regard to leading a disastrous lifestyle;
That is, an antinomian view of a very forgiving Jesus who will rescue fat boomers from a painful wasting away at the end of life, due to poor life decisions.
You're all going to HELL, boomer scum