Wow, somebody got stuck teaching something she really hated, apparently.
I forgot to mention earlier that facts that are imperative for me to know are different from the facts that a different historian might consider basic general knowledge. I can tell you from memory that Frieda Miller resigned as head of the Women's Bureau in November 1953, but I couldn't tell you when the War of the Roses happened within three decades. And your average person on the street has little use even for information about what happened in the twentieth century in more than general terms.
Also, like Womb@ said earlier, much of the information that most adults take for granted was initially learned in high school but reinforced by cultural cues as we go out and experience the world. The more often we hear references to "the patience of Job," the more likely we are to be bale to absorb and recall the context of the comment, if not the details of the actual literary source. How many of us can name the trials visited on Job, or even the book, chapter and verse, wherein they are described? Yet few of us would say we don't know what the phrase "means."
Often, the facts are less important than the accepted cultural understanding of an event. If people, as a whole, believe that the Civil War was about slavery, then doggone it, it was.
Just don't tell the other historians, OK? They'd be awful sad.