A simple question — should adults who are able to work be required to  do so to get taxpayer-provided health insurance? — could lead to major  changes in the social safety net.

The federal-state Medicaid program for low-income and disabled people  covers more than 70 million U.S. residents — about 1 in 5 — including  an increasing number of working-age adults. In a break from past federal  policy, the Health and Human Services Department under Secretary Tom  Price has already notified governors it stands ready to approve state  waivers for “meritorious” programs that encourage work.

Separately, an amendment to the still-stuck House GOP health care  bill would allow individual states to require work or training for  adults, with exceptions such as pregnant women, or parents of a disabled  child.

Yet a surprising number of working-age adults with Medicaid are  already employed. Nearly 60 percent work either full- or part-time,  mainly for employers that don’t offer health insurance, says the nonpartisan Kaiser Family Foundation. Most who are not working report  reasons such as illness, caring for a family member, or going to school.