As Jason Zingale points out in his upbeat review of “The Karate Kid,” Jaden Smith, who’ll be 12 next month, was 11 year’s younger when he filmed his starring role in the new version than the original star, Ralph Macchio. And if, like me, you have to scratch your head when you wonder where Macchio has been since “My Cousin Vinny,” well there’s an explanation.

Well, at least there’s an explanation for why he still looks like he’s just about ready to get out of college despite being three years older than his “Vinny” costar (Marisa Tomei, I mean). It’s possibly related to the fact, against all good Hollywood tradition, he’s been married to the same woman for 23 years, has raised two kids without public incident, and has an apparently clean criminal record. It’s a clear conscience. A very clear conscience. An extremely clear conscience…