The Theme of the Poem
I think that the theme of the poem is that we fear what we don't know. In his poem, Tennyson says, "The Kraken sleepeth: faintest sunlights flee/ About his shadowy sides; above him swell/ Huge sponges of millennial growth and height" (5-7). Tennyson paints a picture of a very frightening creature, describing how it sleeps in a place with no light. He also comments on the Kraken's enormous size. This quote represents that humans fear what they don't know because Tennyson has never seen the Kraken, yet he comes up with scary details to describe a terrifying creature.
Essential Questions
When it comes to the question, "Are monsters created or discovered?" I believe monsters are created. For example, Tennyson has never come in contact with the Kraken; it doesn't even definitely exist. He has painted a portrait of a monster that should never be waken up. Whether something is a monster or not is dependent on a person's point of view. A completely harmless animal may be viewed as vicious by others. Everything is in the eye of the beholder.
http://www.fubiz.net/2012/03/09/the-kraken-existence/