Just Fred wrote:

I interpreted the Pope's words, 'bridges vs walls', as a metaphor for something much more philosophical than physical.

I've been chewing on this all night.
I agree. The Holy Father was NOT denying a country's right and obligation to have borders. He was NOT saying that a country should have no laws controlling immigration.

No, Pope Francis was speaking philosophically. And his remark was brilliant.
The Christian reaches out to the poor and displaced. He helps. The Christian demands compassion in the law. He also looks to improve conditions in Central America such that the poor can have decent lives where they live and are not forced to migrate in the first place. He looks to those decent people working here, obeying the laws, and is concerned about their future. Bridges.

If, when confronted with the poor, a man's only thought is to keep them away, if he denies that the plight of his fellow man is his business,,, if his only impulse is to wall them off,,,,,, well, that is not a Christian.