Memorial Day

I was thinking the other day, is "Happy Memorial Day" an appropriate thing to say? For most people, Memorial Day is something to celebrate because we don't have to work. But the holiday is dedicated to those who gave their lives defending the country, so should we treat it as a joyous occasion like, for example, Christmas or Thanksgiving? I don't know the answer. I'll have to think of it some more... on my day off tomorrow. :-)