Kohl & Feingold

I find it interesting that Senator Kohl voted FOR building the fence on the border. Naturally, Feingold voted against it. (Agreed to: 83-16, 1 not voting.) But when it came to making English the national language, they teamed up again, and voted NO. (Agreed to: 63-34, 3 not voting.) Why is it that the U.S. is the only country (that I'm aware of) that does NOT have a national language? They both decided to vote YES to declare English "the common and unifying language". (Agreed to: 58-39, 3 not voting.) So, what does this tells me? Neither one of our illustrious senators have a clue!