The sisters say they are "united in opposition to the current Republican health care proposals.”

Pope Francis at 80

What makes Sanders' speech special? There is a remarkable convergence between Sanders' criticism of the rapacity of today's global marketplace and Pope Francis'. This should not in itself be surprising.

What Pope Francis' teaches about capitalism, "the free market" and "market ideology" in his en-cyclical "Laudato Si'" is grounded in fundamental biblical insights, consistent with basic ethical principles and in harmony with long-standing and core elements of Catholic Social Teaching

These philanthropists are another group who will be looking for inspiration and challenge from the Holy Father on his visit to the United States.