In this letter from Hemingway to Archibald MacLeish, he has a little to say about Ezra Pound:

Thanks for sending the stats of Ezra’s rantings. He is obviously crazy. I think you might prove he was crazy as far back as the latter Cantos. He deserves punishment and disgrace but what he really deserves most is ridicule. He should not be hanged and he should not be made a martyr of. He has a long history of generosity and unselfish aid to other artists and he is one of the greatest living poets. It is impossible to believe that anyone in his right mind could utter the vile, absolutely idiotic drivel he has broadcast. His friends who knew him and who watched the warpeing and twisting and decay of his mind and his judgement should defend him and explain him on that basis. It will be a completely unpopular but an absolutely necessary thing to do. I have had no correspondence with him for ten years and the last time I saw him was in 1933 when Joyce asked me to come to make it easier haveing Ezra at his house.