Ewan McGregor as Obi-Wan Kenobi

If you’re ever in the mood to start an argument, try telling an adult Star Wars fan that the prequels have some redeeming value. No one wants to hear it, and you can count me among the hardcore Star Wars fans who will not be buying a ticket for the re-release of “The Phantom Menace” in 3-D today. (For a longer analysis of that movie’s impact, check out my article on the CNN.com Geek Out! blog.)

But for all my hard feelings about Episodes I-III, I have to admit that George Lucas got one thing right: casting Ewan McGregor as young Obi-Wan Kenobi.

Sir Alec Guinness will forever be the quintessential Obi-Wan, but it takes a very good actor to make you forget, even temporarily, that Guinness wore that brown robe first. Though Episode I was pretty much a lost cause, McGregor was invaluable to “Attack of the Clones” and “Revenge of the Sith.” He was totally credible as a wise and very patient mentor to that petulant future dictator, Anakin Skywalker. He projected the quiet confidence of a guy who would really rather not take you to school via the Force, but could do so spectacularly if called for.

Frankly, the prequels would have been even less satisfying without him. Whenever McGregor was absent and the story turned back to trade federations or the wooden courtship of Anakin and Padme, I became very aware of my watch. Hayden Christensen may not have been believable as the future Vader, but McGregor inhabited his role in a way that rose above the script and mind-numbing CGI.

One of the best scenes is in “Attack of the Clones,” is when Anakin and Obi-Wan walk into a club in search of bounty hunter Zam Wessel. After telling Anakin to be careful while scoping out the joint, Obi-Wan saunters off toward the bar.

Anakin: “Where are you going, Master?”
Obi-Wan: “To get a drink.”

It seems our Ben was once, as McGregor put it in an interview years ago, “a bit of a lad.”

Scenes like that make me wish that the prequels had gone the route suggested in a great Craked.com essay, focusing more on Anakin and Obi-Wan’s friendship and mutual Jedi badassery than politics and doomed romance. I can only imagine that a better story would have resulted in an even richer performance, and it sure would have given that last light saber battle between the two in “Sith” more emotional heft.

It’s telling that, in a series that chronicles Anakin’s descent into darkness and shows his heartbroken wife dying, for crying out loud, I came away caring more about Obi-Wan. Such is the power of a strong performance. McGregor filled Guinness’ large shoes admirably and provided an oasis of awesome in the desert.