ACLU; What's the "A" Stand For?

I THOUGHT the "A" in ACLU stood for "American." I guess I was wrong. Is it just me, or does it seem that the ACLU works overtime to sabotage Americans and American values? Illegal aliens are NOT Americans. Why does the ACLU concern itself with them? Islamic terrorists captured on the battlefield, are NOT Americans. Same question. I am not suggesting some sort of white supremacist jihad. It just seems to me that the ACLU might devote more of its time, money, and assets to defending the rights and interests of AMERICANS, or maybe change its name. One question I love to ask of my students; "Are you an American first, or a citizen of the world first.?" You would be amazed at the response.