By What Atonement? - God's Failed Plan?

Ideas have consequences, and I wonder sometimes if people were to follow some of their ideas through to their logical conclusion, if they would/could still hold to them.

For the last 2000+ years, the Christian church has preached that the gospel - the good news - is that Christ died in our place, paying the ransom, fulfilling the law, and making atonement for our sin. We were once alienated from God, in darkness, but have now been converted, and born again, through the work of Christ on the cross. He died so that we would have life. The death of Christ on the cross is pretty much the central point of the Christian faith, and without it, we would all still be stuck in our sins and death.

Yet, to read that many in the modern dispensationalist camp teach that the crucifixion of Christ was in fact not the plan, and that had the Jews not rejected and crucified him, that he would have in fact set up the promised earthly kingdom.

I believe the Scriptures teach that Israel could have obtained her much-sought-after messianic kingdom by recognizing Jesus as the Messiah. We all know the sad realty - the Jews rejected Jesus. As a result the kingdom is no longer near but postponed, awaiting Jewish belief. - Thomas Ice, from The Great Tribulation: Past or Future?

If Israel accepted her Messiah, the Kingdom would have been established. - Larry Spargimino, from The Anti-Propheys

These are just a few of the modern teachers that teach this view, that in essence, if the Jews had accepted Jesus as the Messiah, instead of putting him to death, they would have received the Kingdom.

So - the death of Jesus was not the plan to begin with? So, if they had not rejected him, he would not have died, right? So then, what would be the means of our atonement since he would have lived and not went to the cross?

If plan A was to set up a Jewish Kingdom with Jesus reigning rather than dying, and that plan failed with the death of Jesus - causing God to set in mode a plan B, then why are we told in the Hebrew scriptures that Messiah was to die (be "cut off" - Dan. 9:26), and that he should be beaten and killed (Isaiah 53:7-8), among other things? Jesus even knew the plan, because he rebuked Cleopas and the other he met on the road. They seemed to think like today's dispensationalists. They thought Jesus had failed too: "Concerning Jesus of Nazareth, a man who was a prophet mighty in deed and word before God and all the people, and how our chief priests and rulers delivered him up to be condemned to death, and crucified him. But we had hoped that he was the one to redeem Israel.

I guess modern teachers that hold this view should take heed to what Jesus says about their doctrine: "O foolish ones, and slow of heart to believe all that the prophets have spoken! Was it not necessary that the Christ should suffer these things and enter into his glory?" According to modern teachers, they would say "no, it was not necessary!" Jesus then showed Cleopas the answers by opening the Hebrew scriptures and "beginning with Moses and all the Prophets, he interpreted to them in all the Scriptures the things concerning himself." (Luke 24:18f)

So, it sounds like "plan A" was THE plan, and it went down without a hitch, without any postponement, and in fulfilling all of the prophecies of the Hebrew scriptures.

However, if indeed the plan was intended to be a plan without the crucifixion, then we have to ask, by what sacrifice would the required ransom and atonement have been made?