The WDFW (Washington Department of Fish and Wildlife?) has a pretty good web page with useful information for you on moose encounters.

See sections titled "People and Moose" and "In case of attack..."

When I was in Denali in 2006, our guides made it clear that if you piss off a moose, you run the risk of getting stomped to death.

Finally, remember that telephoto lenses are your best defense against unappealing wildlife encounters. Be close up and far away at the same time.