Fluency in other languages is one of the most overrated ideas that our culture is hung up on. Ignorant people are always saying that our kids should learn Spanish because that is going to be necessary in the US with all the immigrants, that is ridiculous.
For one thing, all immigrants are speaking English by the second generation. More importantly, unless you are a contruction foreman or landscaping business owner you really don’t have to know Spanish and you never will. Anyway, we are most interested in professional jobs that require college degrees, you will never need to speak Spanish in this environment.
English is not only the common language in the US but it is accepted as the international language of business. When Japanese businessmen are meeting with Chinese or Korean businessmen, for example, they are most likely talking in English.
That being said, learning Spanish or other languages is a great component of the general liberal arts education. Learning and being functional in another language is also fun if you happen to do a lot of world traveling. But unless you plan to work in Mexico or another Spanish speaking country, you will NEVER have to know Spanish to communicate. Ditto for Mandarin.
By the way, I speak Spanish and have never had to speak it here in San Diego. It is fun to be able to speak Spanish when I go to Mexico, or to watch Spanish TV but it is certainly not a skill that is necessary for most careers.