Last week’s consumer sentiment data flashed a yellow light of caution that the consumer resilience that has powered the U.S. economic engine over the last four years is sputtering. Consumer retail sales in January fell by 0.9 percent from December, a much stronger pullback than economists had expected. The spending decline was broad-based, meaning that even colder-than-average temperatures across much of the country couldn’t completely explain the magnitude of the slowdown.