Plucking officers early has unintended consequences. Immediately after 9/11 in Afghanistan, what went unnoticed was the amount of Bn Cmdrs getting relieved. The common thread was that most of these guys experienced accelerated promotions in the mid to late 90’s due to shortages of Majors. They missed those key developmental assignments along the way to command.
Trying to look at Petraeus’ career path and apply it to the rest of the military is folly as well. Petraeus would have risen to the top regardless. He was the honor graduate in about every school he attended (of note: Command and General Staff College where the Army used to only hand select the best and brightest to attend; now it is the “No Major Left Behind” mentality that permeates so much of society today).
Lastly, I would not consider all of the Generals in the article “failed”. Franks did not anticipate an insurgency with the ferocity that was experienced (no one else did either). Casey did a fine job of building Iraq's security apparatus, which set the table for Petraeus to institute the surge. Sanchez seemed to be adrift though. Not sure if there was any lasting contribution he made to the effort.
“Franks did not anticipate an insurgency with the ferocity that was experienced (no one else did either).”
I don’t really see it as a military commander’s job to foresee the political fallout of a massive victory on his part. He’s there to accomplish what the presiident told him to do—defeat the Iraqi military in this case. It’s up to the president to determine the consequences. As far as no one foreseeing the insurgency that followed, I think a lot of people were aware of the danger, but their advice was ignored.