"Federal employment law should be amended to permit English-only rules. Speaking English is the best way to push assimilation."
While that's true, of course, it often takes some time for new immigrants to learn English. In the meantime, they need to work.
I'm not talking about illegals. But, take for example the Hmong immigrants in the US. They came here by invitation of our government. It takes them, particularly the older immigrants, quite a while to learn the language. They still have to work, though.