Should President Obama have discussed the reasons why he replaced General McChrystal on a national stage?

I've always been told that a leader should praise in public, reprimand in private. Was the President modeling leadership when he told the world why he terminated McChrystal?  I am by no means saying that McChrystal was right in having the reporter from Rolling Stone there to write an article. However, hearing the President say he violated the code of conduct and erodes trust sounds a lot like some of the comments in the article.

What are your thoughts.