There are plenty of good, dedicated linguists in the services -- most of them are properly employed and are not serving as 'terps -- nor should they be. The length of language training for a post pubescent person to get proficiency in a second language starting from scratch is in excess of three years. That is quite costly and to take that person and put him or her in the field with a rifle company in combat would not really be a very good use of resources.

Train 'em for a year and you get marginal proficiency, do an accelerated course and you get less. That is not to say that everyone shouldn't get some basic phrases, they should and good leaders will make them use them but that's a long way from being a translator or interpreter.

Language training at DLI (full disclosure; Farsi student there, BCE, here) includes some cultural adaptation. Speaking from experience, that cultural adaptation is mediocre at best -- because the foreign born instructors are not going to tell you all the bad stuff you need to know. I learned more in 30 days in country then I had in a year at the Presidio. I also learned that my language skill was below marginal, not quite laughable to most Iranians but close (they're very polite) -- and that most of the school graduates I met there and in other countries believed the same was true of their experience

I also spent more time traveling out of Iran and having to deal with Arabic than I did having to deal with Farsi in Iran. Much like a good friend who spent a year learning Viet Namese and a year advising a Montagnard Battalion wherein no one spoke Viet Namese. Or the ASA guy voice intercept guy in Iran who was a Mandarin linguist (he ended up being the Station's chief scrounger)...

Not to mention that all the training in the world won't give you a sense of the nuances and little clues that a locally born and raised interpreter will.

Having watch the USG try to hire interpreters in several languages in various locales for combat use and having watched the performance of some so hired, I noticed that not many local really wanted to take the interpreter job because it's dangerous and their friends and neighbors don't approve. I also noticed that among those hired, cases of divided loyalties were quite common -- leading to a high turnover rate. There also seemed all too often to be a lack of quality; since the job wasn't popular, you didn't get the best and the brightest.

No question that it would be nice to have good 'terps down to platoon level but it's difficult. There are no easy solutions to that -- stick your nose in another nation and that's one of the smaller problems you will accrue. There are other more pressing problems.