I was just a kid when our country celebrated its bicentennial—a few years older than my oldest grandchildren are now. This means they’ll be almost my current age when our country celebrates its tricentennial. I wonder if they’ll look back on today’s semiquincentennial (half of five hundred years) as something magical in the same way I look back on the bicentennial. I don’t remember how my family celebrated that year. I’m sure there were fireworks, whether we drove twenty minutes to watch them over Disneyland or in the other direction to watch them at the beach. I do remember the bicentennial quarters and two-dollar bills; I still have a few of each, keepsakes more than currency. But our class field trip to Disneyland is my stand-out memory. In honor of the bicentennial, the amusement park invited elementary school students from all over Orange County to spend a school day at Disneyland. This was before Disneyland offered unlimited access to rides with admission. Guests purchased ticket...