At the expense of native Palestinian Christians...
Lots of Americans believe in Christian Zionism. OMG, we have to support Israel. The problem is that Israelis don't see things the way they do. Views along this line get stretched out of shape so much that the modern American believer has now become the Jews of old. Keep in mind that when you visit "the holy land" and see all the sites you knew were there all the time that this is not kinship of belief. It's just Jews making money. Israel is more than happy to show you where Jesus was born along with all the popular other sites they have there.
Maybe these people look on it as the price necessary to pay to bring in God's kingdom, making Palestinians collateral damage in the process while American fundies are safe at home. I doubt if the damage will stop there. Due to the inevitability that prophecy is always found false, no kingdom will come and who knows how bad things will get. I'm sure Christians will put the devastation in the Middle East down to prophecies about the Battle of Armageddon and delight in the carnage.