During the Second World War, Rabbi Herzog travelled with great risk to the US, and back, not before he was able to secure a meeting with Roosevelt. Roosevelt smiled and did not reply to the Rabbi's pleadings for a promise to help the Jews of Europe. His biographer records that several people noticed that his hair turned white when he left the meeting, which he perceived as a failure. Following this, he immediately returned home, missing the ride on a ship that was sunk by a U-boat, and taking what was said to be the last civilian ship to cross the Atlantic during the war.