One trillion dollars—that’s how much the government spent last year on means-tested welfare aid, providing cash, food, housing, medical care, and social services to poor and low-income individuals. The food stamp program is the nation’s second largest welfare program. The number of food stamp recipients has risen dramatically, from 17.2 million in 2000 to 45.8 million in 2015. Costs have soared over the same period, from $20.7 billion in 2000 to $83.1 billion in 2014. The most rapid growth in the food stamp caseload in recent years has been among able-bodied adults without dependents (ABAWDs). These are work-capable adult recipients...