I have not read the book. But does Pat assign any blame to the Christians in America who have not successfully shared their faith with those coming to America.
I would think there would be plenty of blame for America's lazy [and racist?] Christians who criticize poor, legal immigrants instead of sharing their faith with them and serving them as the Scriptures command.
Jesus told us to preach the gospel to the whole world. Americas have the whole world coming to them. I think that would be a good place to start.