Why It’s Not Crazy to Buy a Mall Giant in the Age of Amazon

Buying Westfield will improve the portfolio of mall giant Unibail-Rodamco at a time when retailers only want the best shops

The company betting billions to create a trans-Atlantic shopping-mall giant is playing a riskier game than its investors are used to. In a riskier retail world, though, that may be no bad thing.

The mall deal hasn’t gotten much attention, but its dramatic size and breadth, and its timing, during a period of pessimism about traditional retailing, make it worth watching. Franco-Dutch mall giant Unibail-Rodamco, which owns $52 billion of retail real estate in Europe, is set to buy Australian developer Westfield, owner of a $22...