No doubt due to the Rocky & Bullwinkle show, people tend to have a much kinder, gentler image of moose than they should. Moose are big and pretty used to getting their way. They will attack and kill predators (dogs, coyotes), and are more than willing to chase any perceived threat off (e.g. you or a kid).
The local dept of wildlife has suggestions for chasing moose away from your property (fog horns, bags of rocks thrown at it), but they always recommend caution. And offer to relocate any moose who is being aggressive around people.