Is Teaching Any Foreign Language a Fad?

When I read this article, the first that popped into my head was how can teaching any foreign language be a fad?  Sure, there are some languages that are more prevalent than others, but it is still helpful to know at least one other language than English.  I personally wish I knew how to speak Spanish, French, German, Chinese…some kind of language.  Our nation is moving towards a bi-lingual society and it would help teachers to become fluent in at least one other language.  I think this should be a requirement for teacher education programs now, but that is something that is still in the works.  Maybe as a minor degree.  Knowing another language may contribute to teachers been qualified for the positions of the future.