"As we look at the world-class cities around our planet, we face five new urban realities: a crack cocaine epidemic, assault weapons, massive numbers of homeless children, HIV/AIDS and (in the U.S.) what Time magazine has called the browning of America.' The needs of the urban population are greater than ever. . . . As our cities swell with immigrants, I'm reminded that Jesus was born in a borrowed barn in Asia and became an African refugee...