In an op-ed in the San Francisco Chronicle on July 20, 2019, Prof. Peter Irons refutes criticisms from those who object to using "concentration camps" to describe the incarceration of migrants and of Japanese Americans during World War II.

Lamentably, few also know the term [concentration camps] was used by the political and military leaders who ordered and executed the roundup and mass detention of some 120,000 Americans of Japanese ancestry — two-thirds of them native-born citizens — in the wake of the Japanese attack on Pearl Harbor in December 1941.

The political leaders who launched the greatest mass imprisonment in American history freely used the term now hotly debated and decried to characterize these detention facilities. The month after Pearl Harbor, Rep. Leland Ford, R-Calif., urged Navy Secretary Frank Knox and FBI Director J. Edgar Hoover that “all Japanese, whether citizen or not, be placed in inland concentration camps.”

Other officials used the term as well in pushing for the detention of Japanese Americans, which President Franklin D. Roosevelt authorized in February 1942 over the objection of War Secretary Henry Stimson that incarcerating American citizens without criminal charges “will make a tremendous hole in our constitutional system.”

This thumbnail history shows that even before Americans learned of the Holocaust, the term “concentration camps” was often applied to mass detention facilities in which “undesirable” groups of people were confined, the literal meaning of the term.

Today’s migrants, largely from Central America, who cross our borders to seek work or asylum, are being held in what can fairly be called concentration camps.