KT Bailey sews masks for health care providers and others at her home in Silver Spring, MD. (Toni L. Sandys/The Washington Post)

Should we all be wearing masks? That simple question is under review by officials in the U.S. government and has sparked a grass-roots pro-mask movement. But there’s still no consensus on whether widespread use of facial coverings would make a significant difference, and some infectious disease experts worry that masks could lull people into a false sense of security and make them less disciplined about social distancing.