There are two returns spoken of in scripture. One is the gathering of the Church. The second is the return with the church to defeat the forces of the world allied against Israel. With the Church taken out of the way, only the Apostates and the enemy will remain here with the Israelites. That will tip the balance and the entire world will stand against Israel because they represent the truth of God by their very existance at this point.
As for the makeup of Christians in America. You might be surprised in the difference between what is Christian and what claims to be. There's a whole lot of money to be made in expecting 10% tithe offering of income and time from your congregants. It's a great basis upon which to infiltrate and hijack a religion from a secular standpoint - and an easy device for the enemy.
Satan has perverted everything that God has touched in order to decieve the world and mislead them. Christianity was being perverted while the apostles yet breathed. Yet some would have us believe that because a belief is old and said to be christian that it is authentically Christian even when scripture says otherwise. Begging reason and Logic are favorite tools in this. But, we are not to rely on our own understanding. We are supposed to be relying on God and God's word. Isaiah stated the same things the apostles said, if they come with any word opposed to what is known, there is no light in them. Paul stated that if even he himself came preaching a gospel other than he first presented, let he himself be accursed.
The devil don't care. And neither do the religions playing at Chrisitianity. The only thing that matters to them is their power and how they can preserve it. All other considerations are secondary or expendable.
So are you saying that many Christians from different denominations will be left behind?
If the rapture does occur the Gathering of GOD's church Will that be people of any practicing faith? that profess Jesus Christ is LORD and SAVIOUR? and and have fully repented for their sins?
I find this very confusing, of who will be left behind? I cannot beleive if there is a time where people are raptured from the earth that the people left behind Un-Beleivers will continue to Un-Believe given the fact that they will see family members, friends, and people in general totally gone vanished...