People were saying that in the 1960s as well Frodo.
Indeed. It seems like every decade has a new language to learn based on a growing economy or some other world event. In the '80s, everyone had to learn Japanese. In the past decade, it's been Mandarin. During most of the Cold War, Russian was the smart language to learn.
I disagree with the implicit assumption that the same languages should be taught across the entire country.
More than most other curricular questions, the answer should be contingent on local needs and resources: What languages do people in the community use? English and Spanish are widely-spoken enough to be taught almost everywhere, but there's more geographic heterogeneity in the use of other languages, literally dozens of which would be locally appropriate subjects in some part of the United States.
I actually do agree with you. Firstly, I do think Spanish should be taught as a second language throughout the entire country. However, I think there should be requirements to learn a third and perhaps a fourth language. I don't think that should be set at the national level, although I do think the available options should be set at the national level. States and local school boards can thereupon decide which other languages should be available or mandatory.
Personally, I think something very different from English or Spanish should be required as an addition. That would ideally be something from Asia, such as Arabic, Mandarin, Japanese, or something else. I think the best solution is to set the requirements at an early age and have them required henceforth to ensure the best absorption of said languages. I'm sure we're all aware that the best way to learn a language is to start at an early age. The curriculum should reflect that.