As for the Mexican government being "nice" to us as one poster worries about above, it is useful to remember that we took half their country from them back in the day. They are entitled to not want to participate in our overseas military adventures. I am not saying we should give them back anything, just that a little historical sensitivity would help one to understand their outlook - You may have forgotten all about that episode. I guarantee you that they havent.
They haven't participated in "any" overseas military adventures, not even during WWII (except for one air fighter squadron WWII), and that was the world wide war of all wars. If we took half of the Mexican territory way back in the days of Manifest Destiny the U.S. wouldn't have paid them for it, the U.S. would have just taken it. What's with this historical "sensitivity" stuff? Mexico sold it, the U.S. bought it...I haven't forgotten how we got that land. I'd hate to think what all that land would look like today if Mexico still owned it!