arbitrary death and the suspension of disbelief

Various people have told me that they approve of random character death in literature-- the phenomenon in which a character who might have survived and whose death is not foreshadowed is suddenly hit by a stray bullet or a wandering bus-- because people die randomly in real life, often, and so it makes the story seem more realistic. My response to random character death is completely opposite: when a character dies for no apparent reason, I am thrown out of the story. It seems less realistic, not more. One could draw the conclusion that I simply have a more optimistic worldview; but I'm not convinced that that's true, and in any case I want to discuss more literary questions.

Genre

In certain types of adventure story, the hero has a near-death encounter, if not at the end of every chapter, certainly at the end of every novel. In this sort of story, random death is not acceptable: if the hero and the villain could survive being thrown off a cliff, then if the hero's best friend is knocked off the same high cliff by a gust of wind, I will not believe she is dead. I will skim the remaining pages to see if she comes back, and if she isn't in the epilogue, I'll expect her in the sequel. The problem is that if the book's universe admits that people can be killed by forces as weak as gusts of wind, the hero should not have survived the first three chapters. The random death highlights the fact that the author's whim, not necessity or even internal consistency, drives the plot.

Grieving

In real life, when someone dies randomly, everyone is shocked. The best friend, girlfriend, or parent of the deceased mourns; but so do his other friends, his acquaintances, teachers, co-workers, and so forth. Newspapers write editorials. Schools offer counseling to the entire student body. In particular, anyone who actually observes the death will be significantly affected, and will probably take months to recover. In literature, the same thing must happen. Characters must grieve. Furthermore, mourning must not be confined to the viewpoint character. A quick tour of denial-anger-grief-acceptance is not enough, especially when it is accomplished in a chapter or less, after which we return to the main plot. Not only will the hero be angry, so will all his friends. They won't be able to offer wise advice on the mutability of all things, because they'll be too busy locking themselves in bathrooms and crying because they didn't know the deceased as well as they would have liked, and now it's too late.

Getting Random Death Right

Of course, characters can be hit by buses or stray bullets in literature. However, the writer must establish a universe in which people die for no good reason. For instance, in Hitchhiker's Guide to the Galaxy the destruction of the Earth is amply foreshadowed by the destruction of Arthur's house. Connie Willis' Passage is slightly less obvious: it's a book about near-death experiences, of course, but the thematically important points are that the Titanic got hit by an iceberg, that a little kid with a likely-terminal illness is obsessed by the Titanic, and that the emergency room is a very dangerous place. Moreover, after the senseless character death, the remaining characters react: they try in vain to save her, they go to her funeral and rage at the speaker for misinterpreting the victim's life, and though they do try to find some sort of meaning in her death, they're endlessly frustrated with the easy answers.