"Why such an attention to Israel then?" That NPT signature thing is far too thin an ice to stand on. It does not justify Israel having nukes; all it does say is that Israel acquired/built them in secret. The reason for attention is simply this: Especially lately, Israel does seem to behave sanely. Israel is not (or, no more) a secular state; and the religious nuts in power are not trustworthy.
Suspected assailant in car-ramming attack in West Bank shot (Haaretz)
from the article: Iran: World can't block our atomic program while Israel has nukes