In its early days, Amazon developed a reputation for shunning profits as it built market share in its retail business. More recently, Amazon critics have painted an image of the retailer as willing to indefinitely bleed red ink to drive rivals out of business.  

That perception should be retired, judging by the growing profits of its largest, most mature business. Amazon’s operating income for North America, which includes retail sales and subscriptions from services like Prime, reached nearly $2.84 billion last year—more than seven times the profit it generated in 2014. The company has already surpassed that figure in the first half of this year.