Let's start with the "smoking gun" statement from the IAEA that does not exactly smoke:
Prior to the end of 2003....activities [which may be related to a militarised nuclear effort] took place under a structured programme. There are also indications that some activities relevant to the development of a nuclear explosive device continued after 2003, and that some may still be ongoing.
"May" is not definitely. In the analogy of the BBC's Paul Danahar, drawing from the language of a Reuters report, "If the answer to the question 'Do you think she likes me?' was 'strong indications that she might possibly", I would not be off to buy a ring."
But let's examine "may" in the context of the IAEA's 15-page annex, which in the spin of unnamed officials to media this week, became "definitely".