This is an edition of The Atlantic Daily, a newsletter that guides you through the biggest stories of the day, helps you discover new ideas, and recommends the best in culture. Sign up for it here.The United States has long been blessed with a civil-military relationship that is a model of democratic and civic stability. Extremism in the ranks, however, is growing—and dangerous.

At the turn of the century, when the modern web was just emerging and Microsoft was king, a small but growing technology movement posed an existential threat to the company. Steve Ballmer, Microsoft’s CEO at the time, called one of its core elements “​a cancer that attaches itself” to “everything it touches.

Updated at 4:10 p.m. ET on January 4, 2024.When the conservative authors Christopher Rufo and Christopher Brunet accused Harvard’s Claudine Gay last month of having committed plagiarism in her dissertation, they were clearly motivated by a culture-war opportunity. Gay, the school’s first Black president—and, for some critics, an avatar of the identity-politics bureaucracy on college campuses—had just flubbed testimony before Congress about anti-Semitism on campus.

“That film,” my friend Mick Ryan, a retired Australian general, said to me, “should be shown to all senior national-security officials and military officers. It is the most profound demonstration of what happens in the wake of slovenly strategic thinking.”The occasion was a visit to Israel with a small group of military and national-security experts. The film was a 47-minute compilation of videos taken from dashcams, body cameras, and closed-circuit-television cameras.

This is an edition of The Atlantic Daily, a newsletter that guides you through the biggest stories of the day, helps you discover new ideas, and recommends the best in culture. Sign up for it here.Mickey Mouse has long symbolized corporate efforts to control copyrighted material. As of January 1, an early version of the character is at last in the public domain.