Every other Monday at 9 a.m., Don Hladiuk joins a Zoom call with a group of 30 to 45 students. They are eager to learn about space and astronomy, which Hladiuk is more than willing to talk about.

Once again, Ukraine is teaching lessons on how to deal with aggression. Its sudden incursion into Russia, temporarily occupying 400 square miles of Russian territory, has turned the tables on Vladimir ...