A rather substandard offering from a great writer

This was probably the last Stephen King book that I read and that is probably because I found this book to be very disappointing. While my year 12 English teacher would rant and rave against people who read and wrote essays on Stephen King books I don't actually think that Stephen King, as an author, is all that bad. In fact King is quite a good and thought provoking writer, particularly with a lot of his earlier works. He has earned the moniker of a great horror writer, and I must say, deservingly so. It is a shame, though, that English I, or as a matter of fact, a lot of English teachers, tend to dismiss him as little more than a modern hack that writes airport novels.
However, this book is not actually one of his better books. This book comes as one of his later writings, and, as with most writers, the more books that they write, the quality begins to degrade, and I believe that is the case for most authors. Not all authors mind you, because one of my favourite Shakespearian plays was actually one of the last plays that he wrote. However, we are not living in Elizabethan England, we are living in a post-modern world in which we are surrounded my millions of hacks that want to attempt to flog off whatever rubbish they write.
My theory with a lot of modern authors, and it certainly holds true for authors like Stephen King and Terry Pratchet, is that their early writings tend to be of a very high quality, and as such a huge fan base is created, however the more books they publish the less books are actually sold as many of their initial fans drift off to read other authors and begin to search for more original and interesting styles. An author will generally have one style, and while they may experiment and change through their writing life, the style that they use will tend to be the style that continues to come out of their writings. However, a group of fans will tend to stick with this one particular author, and as such they will always have a ready made market for whatever they write.
This is a story about an alien invasion of earth, or at least the initial scouting party. Remember, Stephen King is a horror writer, so while the story involves aliens, there is a still a horror aspect to it. However, I have noticed that while King's earlier books dealt with a more abstract type of horror, while using spiritual entities and monsters, this abstract horror seems to diminish in his later books to the typical monster running around killing people. In this book the monster is called a 'Sh*t Demon'.
What I mean by the term abstract horror though is the use of horror coming from an abstract concept. Take Firestarter for instance: while the story is about a woman with pyrokinetic powers, it is not her powers that create the horror, but the fact that she and her father are forever being pursued by the government so that they can get their hands on her power. It is not the unknown that is horrific in that story, but rather the horror of never being able to settle down and be free from persecution.
The title 'Dreamcatcher' come from a Native American object that is hung above a sleeping person that is designed to catch their dreams. However that is all that I remember of this book with regards to the dreamcatcher. I do remember that it appeared in the book, and played a role in this book, but that is all I can remember. In fact, all I can remember was a nasty alien slug running around the New England countryside killing people and the American Army rocking up to seal off the area and to attempt to capture this alien creature. Personally, that says a lot about the book to me because I cannot really remember any deep themes or more details of the plot than that. Personally, the only reason that I bought it was because I wanted to play one-upmanship with my friend, and in the end, if it was not because of that, I wouldn't have bought the book. I ended up giving away.