I dont think Jake hated Cohn because he was jew. He hated him because he was a fool for falling in love with Brett, just as he did. He hated him because he boasted about having slept with her. Jake also loved Brett, and he wore it so secretly (not to her) and painfully that he was full of anger when he saw his friend being so happy and insistent about it. It disgusted him. How can someone be so eager about a thing that is causing me so much pain? Jake cares about Cohn, he demonstrate it a couple of times, but he couldn’t stand him and his inevitable suffering. In the end, the fact that Cohn was a jew was, in my opinion, just something to hold on to to refer despectively about someone you don’t like. Race and religion are always an easy thing to grab when you want to insult someone. Of course it is wrong, but those were different times. Besides all the drama, the book is wonderfully written, taking you through a beautiful trip from France to Spain in the 1920’s. I’m not an advocate for bull-fighting, but there is a certain charm about the whole thing, and I think it represents everything Hemingway identified as his core, macho, values: dignity, honor, and bravery. Comradery is also an important value all over the book, and it shows how much Hemingway cared about being part of something.