Israel developed dimona before NPT came into effect. So amend it to have Israel as sixth nws and I am sure israel would sign. It's nukes a legitimate at minimum for that reason alone unlike Pakistan who first tested in 74 or India in 72 but when discussing NPT and Iran we should not mention those two states... Why?
Mexico: Death toll 27 after truck hits religious procession (AP)
from the article: Obama: Israel should sign nuclear non-proliferation treaty