When Donald Trump made his first visit to the Vatican last month, among the gifts he received from Pope Francis was an autographed copy of the pope’s letter Laudato Si’ on caring for the environment. Whether the president managed to read the letter before deciding to pull the United States from its commitment to honour the Paris Agreement on climate change is unclear.

Time will tell whether Mr Trump can make America great again by turning his back on the rest of the
world. But in writing as he has on care for our common home, Pope Francis has made it clear that no nation on earth can achieve greatness on its own terms. Solidarity is the clue to his view. All life is interconnected, and we can fulfil our own destiny only by respecting and upholding the rights of all other beings to their place in our world. There is a moral dimension to which all political and economic decisions must be aligned if they are to stand and survive the test of time.