Hopkins served as an important foreign policy adviser and diplomat during World War II . He was a key policy maker in the Lend-Lease program that sent $ 50 billion in aid to the Allies ; Winston Churchill in his memoirs devotes a veritable panegyric to this " natural leader of men " who had " a flaming soul " . Hopkins dealt with " priorities , production , political problems with allies , strategy — in short , with anything that might concern the president " . He attended the major conferences of the Allied powers , including the Cairo Conference , the Tehran Conference , the Casablanca Conference , and the Yalta Conference . His health declined after 1939 due to stomach cancer , and Hopkins died in 1946 at the age of 55
Yalta Conference
Yalta Conference
Harry Hopkins