He was the U.S. ambassador to the Dominican Republic, Panama, Turkey, and Iceland, where he worked on issues ranging from regional stability to the implementation of the Truman Doctrine.
However, his legacy is mixed, as his tenure as chief of the Visa Division coincided with restrictive immigration policies that hindered Jewish refugees fleeing the Holocaust.
While Warren’s role was largely administrative, historians note that his leadership coincided with a broader systemic failure to provide refuge to those fleeing Nazi persecution.
He played a key role in maintaining strong bilateral relations and ensuring the canal’s security during the final years of World War II and the early postwar period.
His efforts focused on reinforcing Iceland’s strategic partnership with the United States and its role within NATO’s Cold War defense strategy.
As chief of the Visa Division, he oversaw immigration policies that have been criticized for their rigidity and lack of compassion toward Jewish refugees fleeing Nazi persecution.
Unlike some diplomats who actively worked to assist refugees, Warren’s actions reflected the priorities of a system that placed national security concerns above humanitarian considerations.
Warren’s life and career serve as a lens through which to examine both the successes and shortcomings of American diplomacy during a transformative period in global history.