Two prominent U.S. senators have criticized Amazon’s heavy-handedness in erasing a bestselling book by scholar Ryan Anderson on transgenderism.

Sens. Marco Rubio (R-FL) and Josh Hawley (R-MO) have blasted the online tech giant for its overt censorship of uncomfortable ideas by de-listing Dr. Anderson’s When Harry Became Sally: Responding to the Transgender Moment.

“American oligarchs, cheered on by leftist politicians, are conducting digital book burnings,” Rubio tweeted Tuesday. “@Amazon banned a thoughtful & well researched book on a complicated issue.”

As Anderson confirmed with Breitbart News Tuesday, Amazon cancelled the book, not because of factual errors or inflammatory language, but rather because it rationally counters the gender ideology popular in certain progressive circles.

“The corporate left begins the banning of books. Openly and without apology. Welcome to the new normal,” Hawley tweeted in response to a comment warning of the problem when one of the world’s biggest corporations begins “deciding what constitutes ‘appropriate’ thought & information.”

In his tweet, Rubio linked to a Wall Street Journal op-ed by the editorial board decrying Amazon’s arbitrary removal of Anderson’s book.

In the essay, titled “Tech Censorship Is Accelerating,” the WSJ editors noted Amazon had “purged” Anderson’s 2018 book, which “criticizes recent progressive ideas about gender and especially the wisdom of sex-change procedures in children.”

“Amazon declined comment on the reasons for the ban, but comment is hardly needed,” they observed. “The tech companies have grown increasingly open about their ideological censorship.”

“Corporate media censorship, such as Amazon’s scrubbing of a heretical book, is accelerating,” the editors noted.

The book explores the biological, psychological, and philosophical backstory to the transgender debate.

It has received numerous positive reviews from doctors and professors of psychiatry, psychology, and medical ethics at universities such as Johns Hopkins, Boston University, New York University, and Columbia University.

As Breitbart News has noted, Amazon’s decision to de-list Anderson’s book came just days before a congressional vote on the Equality Act, a piece of legislation Anderson opposes.