I'm not a lawyer, but it seems to me that even if the owner of a robot
that inflicts significant damages on a site is not legally culpable,
he/she could still be financially liable for civil damages.
This is not meant as a defense of xxx.lanl.gov. The tactics there are
extreme and bizarre, starting with the skull and crossbones at the top of
the page.
The HTML code for the xxx.lanl.gov page contains the following comment
at the bottom of the page:
"despite the name, this site has no relation to or information on
any of the following topics: sex, adult, nude, playboy, porn,
porno, erotica, pornography, erotic. gay, penthouse, pussy willow,
bondage, girls, xxx, nudity, nudes, hustler ..."
This suggests to me that they have brought much of their trouble on
themselves by continuing to use the name "xxx".
-Gordon Bainbridge