Alphabet finally crashed tech’s most exclusive party. On Monday, Google’s parent company became only the fourth U.S. firm ever to hit a $3 trillion market value when it touched that number in intraday trading, a milestone that caps months of investor hand-wringing over antitrust pressure and proves that Wall Street is ready to give the company more credit for its AI ambitions. Shares jumped more than 4% to record highs, lifting both of Alphabet’s publicly traded classes into the three-comma club. That put ...