The article seems to be talking about the almost dumbest of the dumb "Category IV" recruits, not the merely dumb. Prior to the Iraq war (when this article was written), the military more or less kept this category out:
> on Sept. 20, 2005, the Defense Department released DoD Instruction 1145.01, which allows 4 percent of each year's recruits to be Category IV applicants—up from the 2 percent limit that had been in place since the mid-1980s [emphasis mine].
> Independent thought,or intelligence in general, are strongly discouraged unless you're lucky enough to be in one of the tiny,incredibly rare units that does something interesting.
Are you sure you're talking about intelligence? It sounds like your really talking more about independence of thought and obedience.
I could totally see the Army valuing obedience over intelligence, while still highly valuing intelligence (e.g. intelligence applied to fulfilling orders rather than questioning them).