Under what circumstances would ISNIC close or delete the domain wikileaks.is based on the contents of their website?
The answer is simple, such an action would require a formal court order from an Icelandic court. ISNIC has never been handed such a verdict about any .is-domain during its close to 25 years of history.
ISNIC is not responsible for the registrant's usage of his/her domain, the contents of email sent from the domain's email addresses (e.g. email@example.com) or the content of the domain's web pages (e.g. www.wikileaks.is). It is ISNIC's duty and prime function to maintain uninterrupted service to all .is-domains, at all times, anywhere in the world. Only Icelandic authorities, armed with a court order, can order ISNIC to delete or close down a particular .is-domain. This has, as said before, never happened.
Registrants (who've read our Rules and FAQ) know however that domains may be closed for two main reasons. Once closed, the system will delete a domain automatically pending a 60 day grace period. During this process the domain's contacts receive multiple notices and warnings. The reasons for closing a domain are: non-payment of the domain's fees, or if the domain's registration or technical setup is not according to ISNIC's specifications, rules and regulations. So, in short, the only way wikileaks.is would be closed (and eventually deleted) by ISNIC is if its registrant would not renew the domain or if it's technical DNS setup and/or whois registration would no longer be according to ISNIC's registration rules.