America’s next president could be eased into office not just by TV ads or speeches, but by Google’s secret decisions, and no one would know how this was accomplished. Research I have been directing in recent years suggests that Google, Inc., has amassed far more power to control elections—indeed, to control a wide variety of opinions and beliefs—than any company in history has ever had. Google’s search algorithm can easily shift the voting preferences of undecided voters by 20 percent or more—up to 80 percent in some demographic groups—with virtually no one knowing they are being manipulated, according to experiments I conducted recently with Ronald E. Robertson. Given that many elections are won by small margins, this gives Google the power, right now, to flip upwards of 25 percent of the national elections worldwide...