TOKYO – On any list of things Xi Jinping feared might spoil his desire for a third term as Chinese president, runaway inflation probably didn’t warrant high placement. But now, the fastest factory inflation in 26 years is complicating Xi’s best-laid plans. And there’s an even bigger complicating factor: signs of overheating in the US, where consumer prices are rising at their fastest clip since 1990. China’s inflation troubles are one thing. But a 6.2% jump in consumer costs in the US, the issuer of the reserve currency, is a far bigger threat to China given the symbiotic nature of the world's two biggest economies. And a dearth of optimism about smoother Group of Two relations with Joe Biden’s White House hardly helps. The latest inflation numbers belie arguments by US Federal Reserve Chairman Jerome Powell and Treasury Secretary Janet Yellen that inflation pressures are "transitory." Indeed, they could end up being right. But the trajectory of prices throws cold water on the theory that base effects from last year’s Covid-19 recession tell the full story.