A year ago, Jonathan Anderson staged his hot-ticket Dior debut in Paris inside a massive tent at the Hôtel National des Invalides, showing billowing cargo shorts, schoolboy ties, and rakish military jackets. For his sophomore Dior Men’s spring show on Wednesday morning, the designer threw a house party in the stately rooms and leafy backyard of the Musée Nissim de Camondo, a decorative arts museum by Parc Monceau.
“It’s been the first year now in the brand, so I was thinking to…

