People all over the world work very hard to learn English to communicate with us. We can always find an American who is a native speaker of whatever language.
In WWI and WWII American GIs who spoke German were of great usefulness at all levels.
The Codetalkers during WWII were the key to communicating with our forces in the Pacific in code that Japan was never able to break.
During the Cold War, college students who could speak Russian were recruited for many sensitive positions.
In today's economy, more and more jobs list bilingualism (at least) as a requirement for application.
etc. etc.