If President Obama’s planned “call to unity” and pledge to work on centrist initiatives in his second State of the Union speech don’t have you itching to tune in Tuesday night, don’t feel too bad. Not many of your fellow citizens will watch, and even if they do, they’re unlikely to remember what it was they heard....

“They’re not defining moments for presidents,” says Julian Zelizer, a professor of history and public affairs at Princeton. “There are a few times when the way events unfold later make something a president said memorable. I’m not sure you can know it when you see it.”

It’s not just the boring, laundry-list format that’s driven viewers away: it’s the fact that viewers have a choice. Although the number of broadcasters carrying the speech has nearly tripled in the last 20 years, anyone who turns on the TV Tuesday night will have a far greater range of choices—unlike the glory days of network television, when anyone who wanted to watch the tube had little or no choice but to watch the president....