Technically, it already is. The library [libdvdcss] for decoding the the disc is illegal in the US (under DMCA), although its legality has never been tested in court. Well, it was sent to court in Norway, where the DVD CSS was cracked, but the case was dropped. But its out in the wild so its a moot point.
There is a difference. Currently, breaking the DMCA for personal use is a civil matter. You can be sued, but you aren't going to go to jail.
This new law makes possession of the tools needed to break copy protection a federal crime with a penalty of up to 10 years in jail.