Sundar Pichai, chief executive officer of Alphabet Inc., during the Bloomberg Tech conference in San Francisco, California, US, on Wednesday, June 4, 2025. David Paul Morris | Bloomberg | Getty Images Alphabet briefly passed Nvidia by market cap in after-hours trading this week, a remarkable feat for a company that was seen as deeply at risk in the early days of the artificial intelligence boom. The stock is up about 160% in the past year, driven higher by an emerging view on Wall Street that Google is well positioned across the AI landscape, whether it's from the company's homegrown models, its massive distribution network or its cloud unit that's reeling in cash from other booming AI businesses. Among tech's seven other trillion-dollar companies in the U.S., chip designer Broadcom is the next best performer over the past 12 months, with its stock up 107%.…