In mid-2004 the Department of Defense conducted a survey of linguistic skill among military personnel (including Special Forces and intelligence specialists), focusing on a dozen languages deemed most critical given current operations and possible future commitments.
Farsi (Iranian) 892
Note the curious absence of Urdu and Pushtu, the two most common languages in Pakistan. Pushtu is also the language spoken by the largest minority in Afghanistan (about 40 percent of the population), and the tribes that provide most of the support to the Taliban.
Given that the U.S. has been deeply involved in the Middle East for several decades, not to mention having fought a war there in 1990-1991 and another since 2001, or that we've been worried about a war in the Far East for decades now, the figures suggest a distinct failure to have learned the language lesson of Vietnam.
Moreover, most of the personnel listed are native speakers, either immigrants or the offspring of immigrants, as can be seen by the very large Spanish speaking contingent. The large Filipino speaking group is the result of the special arrangements that permits citizens of the Philippines to serve in the U.S. armed forces.
The Department of Defense is finally trying to come to grips with this problem. An aggressive program to recruit immigrants and the offspring of immigrants has been initiated. In addition, there is some talk about making skill in certain languages a mandatory requirement for officers, something for which they would have an impact on their career prospects.
If such a program is initiated, officers would be ordered to lean a specific language. This would put significant organizational, cultural, and personnel management strains on the Armed Forces. It is generally considered that most people require two to three years of fairly intensive instruction to become reasonably fluent in a language of which they had hitherto had no knowledge. And some people are quite literally incapable of learning a new language.
Reportedly, when the U.S. began to become seriously involved in Southeast Asia, in the early '60s, there were, in the entire Armed Forces, only three officers with a working knowledge of Vietnamese. Were it not for the large number of military personnel who spoke French, in which most educated Vietnamese were fluent, the war effort would have been seriously handicapped. One would think that lessons would have been drawn from this. Unfortunately, they were not.