Hours after West Point pulled its offer to have her teach cadets, Jen Easterly posted a short essay in which she laid out what happened to her and what it meant for the country.

“This isn’t about me,” she wrote last week. “This is about something larger.”

Over three decades, Ms. Easterly, 57, had compiled an impeccable résumé as a West Point graduate, a Rhodes Scholar and an Afghanistan war veteran. She had served as a key aide on President George W. Bush’s National Security Council and led a critical cybersecurity agency under President Joseph R. Biden Jr.

Now she was blackballed — in her own words, “a casualty of casually manufactured outrage that drowned out the quiet labor of truth and the steady pulse of integrity.”

The source of the casual outrage arrayed against her was Laura Loomer, a right-wing agitator and self-described “Islamophobe,” who has become a powerful and largely unaccountable enforcer in President Trump’s Washington.

“Wow @PeteHegseth! Looks like some of your underlings are trying to screw you,” Ms. Loomer wrote on X on July 29. She accused Ms. Easterly of using her position leading a cybersecurity agency in the Biden administration to “silence Trump supporters” who questioned the integrity of U.S. elections.

The next day, Army Secretary Daniel Driscoll, an Iraq war veteran and Yale Law School classmate of Vice President JD Vance, announced that Ms. Easterly would no longer serve as the Robert F. McDermott Distinguished Chair in the department of social sciences at West Point.