Commentary President Joe Biden blames inflation on supply chain problems. He has assured the American people that since supply problems will lift soon so will inflation pressures. He is wrong on both counts. The inflation reflects more than supply chain problems, but even if it were just supply matters, they will persist longer than he claims. The nation’s supply chain difficulties have many moving parts, but their root lies in the post-pandemic buying surge. Consumers, having spent little during the lockdowns and quarantines and sometimes with generous government checks in hand, have ratcheted up buying since the strictures have eased. Overall consumer spending has grown a powerful 11.6 percent over the past 12 months, a rate of increase only surpassed by the initial, post-strictures buying surge during the summer of 2020. The demand surge has filtered back from retailers to producers who, having stopped or curtailed activity during the lockdowns, …