The Kingdom of Clowns — David Niall Wilson

Young William O'Connor Bartholomew Rufus wanders through two worlds. One is the normal, everyday world we all know so well, and the other is a place of wonder. In that magical place, he can shift his surroundings as easily as he changes his hats, imagining things a bit differently each time. William grew up to serve in the United States Navy, but his dad remembers that other place fondly, and so he has captured it here in this book with his friend Dan, the artist. No matter how many miles apart they might be, they are still only a "hat" away.