Here's a fun(?) game to play: pick a random US president from at least a century ago. No, not someone like Washington or Lincoln, but let's say... Rutherford B. Hayes. Now look up the major event during his presidency. For Hayes that would be... the Great Railroad Strike of 1877. Now ask yourself, what do you know about that event?
Now, unless you are more up on US history than we are, or are trying to be clever (well, obviously, in 1877, the railroad workers went on strike!), you probably don't know. As, let's face it, you wouldn't know most historical facts that were once thought important.
Now, imagine you're someone living 100 years from now. Pick a 20th century president and a major event during his term. Say, LBJ. Sure, everyone will (likely) remember the Vietnam War, but will the Civil Rights movement get lost in the shuffle? The Equal Pay Act, the Civil Rights Act, the Women's Strike for Equality (well, obviously, the women went on strike... for equality!), all keystone moments of our time, will they be forgotten? And will names like Betty Friedan, the woman whose role in all of those was vital, be lost to history?
We definitely hope not.
But, alas, we can't be certain...