Should governments have a language policy for a particular nation?

Many times over break i have witnessed a communication barrier between people. Recently someone i know got into an argument with a Spanish maid that worked for her. The argument escalated quicker and quicker and part of that reason was they couldn't understand each other. This was a big problem and led to the maid getting fired. I believe that if our government was more strict on enforcing a single language for all citizens to know, incidents like this wouldn't happen. In this case it resulted in a loss of job, but much worse things could happen such as a physical fight over something as simple as a miscommunication. This is all easily avoidable if everyone in the country is fluent in one singular language. I also believe that this language must be the only language spoken in public. Many times if one group is talking in a different language in public, it can lead to suspicion of why they wouldn't want everyone to hear it. I still think it is important though that multiple languages are taught in the classroom and privacy of a home. But, i do think that the United States government should enforce the policy of a single language.