The move is the latest step by the Defense Department to target pro-diversity content and programs -- an effort that led to the removal of troves of documents and images from its website and swept up articles on African American pioneers such as the Tuskegee Airmen.

"Educational materials... promoting divisive concepts and gender ideology are incompatible with the department's core mission," said a memo to senior Pentagon leaders, military commanders and other officials.

The memo directs officials to "promptly identify any department... library materials potentially incompatible with this core mission," sequester it for review and "determine an appropriate ultimate disposition for those materials."

It said a committee of "knowledgeable leaders, educators, and library professionals" had compiled a list of search terms to identify materials for review.

The list, which appeared in an attachment to the memo, includes: Affirmative action, allyship, anti-racism -- United States, Critical Race Theory, Diversity Equity and Inclusion, gender nonconformity, gender transition, and transgender people -- United States, among others.

"The subsequent deliberate review by experts in the fields of education and the department's mission will determine the ultimate disposition of the material, based on the totality of the circumstances and findings of relevant facts," the memo said.