For many decades, low oil prices would help the U.S. economy. Not so much anymore. The cost of West Texas Intermediate crude oil is around $26 a barrel, having tumbled from roughly $60 at the start of the year. That sort of price plunge used to mean that drivers could expect their gasoline expenses to be cut in half and for the economy to benefit. But as fracking has boosted America’s energy production, lower oil prices have led to less drilling, less manufacturing and more layoffs. And those job cuts have begun to mount in states that long depended upon oil-related jobs. Texas records show that the Houston-based energy services firm Halliburton plans to furlough 3,500 workers for up to 60 days. A steel pipe manufacturer is letting go of 223 workers in Harris County. The energy company Apache is laying off 85 in Midland. And that’s all in the past week. For America’s economy, depressed oil prices are clearly no longer a boon but a threat.