US Ambassador to the Holy See Brian Burch (L) welcomes US Secretary of State Marco Rubio (C) upon his arrival at the Rome's Ciampino airport on May 7, 2026. America's top diplomat, Marco Rubio, will visit the first US pope, Leo XIV, seeking to ease tensions between Washington and the Vatican while also promoting President Donald Trump's interests. (Photo by Andrew Medichini / POOL / AFP via Getty Images)