What made it worse is that Roosevelt and Chamberlain were allegedly part of the Christian sect that believes in the literal truth of Revelations i.e. that the region must be in the hands of the Jews so that the faithful can be raptured to Heaven.
F.D.R. and Neville Chaberlain? Well, no, we can reasonably say that if they
were they did a fantastic job of hiding it as there's no evidence their religion leaned in this direction. They were also a little busy being dead when Israel was set up, which wasn't done at the behest of Britain - although settling the Jews there dates all the way back to World War I and the Balfour Declaration. The same Balfour who took a rather dire view on Ireland, ironically, but hey, it's funny how these various sectarian problems can intersect like that.
Balfour's appeal did include a Christian element, but more of a general Christian sentiment that the Jews were God's chosen people and not exactly that their occupation of Israel will bring the Rapture, which is a tenet of thought fairly unique to American theology.