141 The true worth of the different countries of our world is measured by their ability to think not simply as a country but also as part of the larger human family. This is seen especially in times of crisis. Narrow forms of nationalism are an extreme expression of an inability to grasp the meaning of this gratuitousness. They err in thinking that they can develop on their own, heedless of the ruin of others, that by closing their doors to others they will be better protected. Immigrants are seen as usurpers who have nothing to offer. This leads to the simplistic belief that the poor are dangerous and useless, while the powerful are generous benefactors. Only a social and political culture that readily and “gratuitously” welcomes others will have a future.
Source: Fratelli Tutti (Vatican.va)