Go Figure

After reading this article this afternoon, the last paragraph has me a little confused. I am trying to do this the easy way, so I don't know why this is becoming such a problem / uproar........

And let me tell you, from the statements that I've read, any person who has stood in an immigration line and has done everything needed to reach legal immigrant status seems to support Arizona and the bill that they are getting ready to enforce regarding illegal aliens. I think any person with papers would be mighty proud to show them if asked about their status instead of this:




So, this is where I need a little help figuring. This is the last line of the article.

"The White House has indicated that it's prepared to go to court if necessary in a bid to block the new law, which makes it a state crime to be in the country illegally."

The dictionary defines a crime as "an action or instance that is legally prohibited." Isn't it already a crime? It's just a bill that says we are finally going to enforce a law that's existent in every state of the union. It's just not enforced anywhere else. And why, again, is this such a bad thing to enforce the law........