Was North Korea's "cyber attack" a threat.

As I'm sure whoever is going to read this blog, you've probably seen the movie the interview. If you haven't its basically a comedy movie about plotting the assassination of North Korean Leader Kim Jong Un. The promotional campaign of the movie was one of Hollywoods top campaigns. Once the previews were out a little while, and once North Korea found out about the movie there was a cyber attack on Sony Corporation. The country of North Korea was able to hack into Sony Corporation's computer records and disable every computer from the corporation. They were able to get every file about everyone that was in sony, which gave social security numbers, emails and private information. They also made a threat on the United States, that any movie theatre that screened the movie on Christmas day, North Korea was going to bomb up it. When Obama heard of this issue, he stated that the United States does not back down to threats and movie theatre's all around the United States showed the movie on Christmas day, and the movie was available pretty much on every movie website online. As far as the cyber security issue.. did North Korea do this to prove to the United States that they are technologically capable of such a cyber attack? or did they do this and have intentions of using this information in a negative way against the United States????

http://en.wikipedia.org/wiki/Sony_Pictures_Entertainment_hack