California Governor Gavin Newsom on Thursday ordered the state’s some 40 million citizens to “shelter in place,” meaning they shouldn’t leave their homes except to perform essential activities such as picking up food or medicine.

Then on Friday Governor Andrew Cuomo of New York ordered all non-essential businesses to keep their workers home, as did Connecticut Governor Ned Lamont. Governor Philip Murphy of New Jersey said he would do so on Saturday. These actions got a federal imprimatur when Dr. Anthony Fauci of the White...