Vuitton, Dior, and Alyx are making major fashion statements with great bags. This is not your father’s murse! Imagine one of those evolution charts in which a primate, moving on his beastly hindquarters and fists, morphs into a highly intelligent human being, striding proudly on two legs. Now imagine it for men’s bags. (Isn’t science fun?). On one end is your sad, coffee-stained New Yorker tote—“I’m carrying a bag, but it’s really a badge that proves I’m an intellectual!” In the middle, the fanny pack, slung across the chest: “I’m carrying a bag, and it’s for fashion!” And at the most highly evolved stage? We are living in that very moment now. Men’s bags have finally become…human. Which is to say: the fanny pack is now generating almost 25% of accessories growth in the United States, and that’s not because women are cuckoo for clout packs. Since skaters, and then fashion editors, started slinging the bum bag across their chest, the idea of a pouch that essentially functions as a clip-on vest in which to carry stuff—a midlayer garment—has become a welcome addition to the men’s wardrobe. It isn’t merely that men seem to be driving design and sales shifts in the handbag mark...