The profound motivation of Julian Assange for doing WikiLeaks?

In 2007 he wrote on his blog:

That latter path can be hard to find, because it is only satisfied by creating ideas or inventions that have a global impact. Perhaps I have found one, and there’s others out there, but for most people of your character a combination of eschewing knowledge of those parts of the world they can’t change, and robust engagement with the parts they can is probably optimal.