What are the pros and cons with the new law in arizona?

There is the problem the Bill doesn't only effect Mexicans it effects all people, Imagine if you are black and driving in Arizona and forgot your ID they can arrest you, detain you until you prove you are an American citizen. To me it's another attack on our constitutional right by republicans, just like the Patriot Act. The republicans singled out Mexicans when ping this bill, but it will effect every minority Arizona, wait and see.