This is not the column I expected to write this week. But a few nights ago, I had an experience that confirmed for me that we're on the cusp of history — regardless of how the Supreme Court decides, in the landmark marriage equality cases it's currently deliberating.

I was at dinner with my mom and dad, belatedly celebrating (if that's the right word) my 45th year on this planet. I love my parents and enjoy spending time with them, but I'm always wary of that moment — usually between dessert and the arrival of the check —...