In February, I was browsing the shelves of our local secondhand bookstore, looking for birthday gifts for two grandchildren, when I came across Hermann Hagedorn’s “The Book of Courage.” This 90-year-old collection of biographies for young people salutes luminaries as diverse as Clara Barton, Daniel Boone, David Livingstone, Mahatma Gandhi, and Queen Elizabeth I. Here, too, are figures our culture has canceled or derided in the past decade, men such as Andrew Jackson, Robert E. Lee, and Abraham Lincoln. The years and the fingers of earlier generations have left this volume tattered and worn, but for $5, it was still a bargain. Today it sits on my “grandkids’ shelf” in the living room, awaiting new explorers of the past. Frequently, readers write me asking for book recommendations for students, particularly those having to do with history. Despite “cancel culture,” we can still find excellent accounts of our nation’s past for …