The Labor Department reported Friday another solid month of U.S. hiring in July. Getting less attention these days, but no less important, is how little American firms are firing.

Americans are less likely to be laid off than at any point in at least 50 years. For every 10,000 people in the workforce, 66 claimed new unemployment benefits in July, trending at the lowest point on record going back to 1967. The previous low point, 83 per 10,000, was touched in April 2000, at the height of a tech boom. Separate Labor Department...