English-only?

I had a knee-jerk negative reaction to the passage of the English-only law here in Missouri. Since from what I understand it won’t change anything about how the state operates, it seemed to have no point other than to let people express their xenophobia. That is, it just seemed rude. However, the other night I discovered that several folks I know and admire voted for it and support the idea of English as America’s official language in general. And not out of any anti-immigrant feeling but almost the opposite: one person said that giving immigrants language crutches would keep them from learning English and hurt their opportunities here. Another said simply that with the great diversity of America, we need a minimum of common culture, such as all being able to speak English with each other. So obviously I was wrong about the motivations of at least some of the people who voted for the law, which given the overwhelming majority of the Yes vote is a relief. The principle itself I’m still not sure about. As always I welcome your thoughts.