Definitely a possibility, and surely the most likely outcome, but as an Open Theist, I'd like to think that it's possible, however unlikely, for Christ to return to a Christian-dominant society.
I don't think that the Bible allows for that outcome.
I'm not saying that there will be no trial by fire of Israel, just that the number of Christians in the world could be much higher.
Here's the possibility I see.
Society collapses, while Christianity survives, and enough to rebuild society. Time passes, and most (not all, but certainly more than 50%) of people are or become Christian through the spreading of the gospel. Even Israel turns to God and repents, so Christ raptures the church, and what remains is less than half the population of the earth, including Israel. The rest is recorded in Revelation, though not on the scale it would be if Christ were to return in the next few moments, with most of the world currently being against Him.
The population of earth is currently just over 8 billion people. Subtract the percentage of Christians from that number, and you'd have a greater amount, and thus, more people in rebellion against God during Revelation.
My idea is that if Christianity were to become dominant on the world, or even if it was just 50% at the point of the Rapture, would result in far less carnage.
I think it's plausible, and certainly worth striving for, since it's never a bad thing to win people to Christ, even if unlikely.