What Makes "Art"?

I was reading an article today about how Japan is restoring the only tree that survived the Tsunami that hit last March. When i was reading this article, i got to thinking about how i now viewed this tree as a work of art. The fact that this tree was just a regular old tree that no one looked twice at, and probably also didn't pay much attention too immediately following the disaster either, is now a symbol of hope and strength. This was the only tree that survived, and the image in the article is a powerful one. The tree has been damaged since by the salt water, so Japan is restoring it by putting a carbon spine in the trunk and plastic replicas of the leaves, and then returning it to the original spot. This tree is now a work of art to me, the fact that it stands for something more than itself and the fact that people identify this tree with the strength of Japan and value it enough to spend the equivalent of $27 million on it shows that this tree should be valued as Art. It sparked my interest in how this phenomena happens, through events... regular objects can be turned into art. What do you think?

Here is a link to the original article, which provides an image worth seeing!
http://news.yahoo.com/miracle-pine-tree-removed-tsunami-ravaged-city-133025066--abc-news-topstories.html