If it's any consolation, non-Americans, no one actually celebrates these days. Memorial Day would genuinely be more fitting if it was titled "Barbecue Day" or "Cook-Out Day." The only thing that most people notice about Memorial Day is the flags flying at half-mast, and I spoke to quite a few people yesterday that couldn't even figure that puzzle out.
Independance Day is the only one where most people actually do something (watch the fireworks), but we don't even call it that here. Everyone refers to it simply as "The Fourth of July," which I think is sickeningly kiddish. The rest of them no one really cares about. Their main purposes are for people to create small-talk by sparking conversation with, "We really should have gotten today off for [insert "holiday"]."