Just when the United States started to make some progress reversing decades of mass incarceration, Democrats want to lock up people with mental illness in the name of compassion and care.

New York Mayor Eric Adams called it a “moral obligation” to hospitalize people against their will if they are a danger to themselves. His proposal has police officers assessing whether a person is mentally ill.

In Portland, Ore., Mayor Ted Wheeler recently told a roomful of business leaders that he wanted to lower the threshold for involuntary commitment of people who are both mentally ill and homeless, declaring: “They need help, and they need compassion.” The outgoing director of the Oregon Health Authority echoed Wheeler, calling for expanding the capacity of the Oregon State Hospital, the site of the 1975 film “One Flew Over the Cuckoo’s Nest.”

In California, Gov. Gavin Newsom has signed legislation that would allow family members and first responders to mandate treatment or involuntary commitment.

Incarcerating those perceived as mentally ill is not a new idea. In the 19th century and the first half of the 20th, hundreds of thousands of people were forced into mental institutions and hospitals. Many of them were immigrants deemed a danger to the broader society. Then and now, removing people from our communities to be put in institutions has been a project of social control.

In the 19th century, asylums, charitable hospitals and almshouses emerged as part of a reform movement to provide “moral treatment” to the poor and the ill. The very meaning of the word “asylum” — sanctuary or retreat — suggested a “therapeutic landscape.”

Then, in the Progressive Era that began in the late 1800s, eugenics — the science of improving humanity by “breeding out” disease and undesirable races — gave these institutions a new mandate: to protect healthy and “well-born” citizens from the biological dangers of mixing with people labeled “feebleminded,” “mental defectives” and “lunatics.”