Did he really put Australia in the same category of dangerous "rogue states?" 
Or is seeking nuclear weapons all that is needed to classify a country as one?
That's the point - none of the three countries named in the article are developing nukes - If Australia wanted them, it'd be a simple matter of walking down to ANU or Lucas Heights and asking for them. We could have them and a working ICBM delivery system in six months, twelve tops. South Africa is the only country in the world ever to give up Nukes, and Argentina has a bilateral inspection program with Brazil, so I doubt they're trying for them. It's like he's just picked random countries from a hat.
Many FSU countries gave up their old soviet nukes when USSR collapsed and returned them to Russia. South Africa, Argentina and Brazil you mentioned; Sweden dropped their own program in the 60s if my memory serves me right. Israel is in grey zone.
Pretty much every single wealthy first world nation could make nukes pretty easily, it would be 6-24months program and then they would have them - if they wanted to. It's not a question of "how", it's a question of "why" - needed know-how exists. It's the poorer countries who have problems, but even they can build nukes.
His point is actually quite valid. More nukes = increased propability of someone using them or them falling into wrong hands (although nukes are insanely powerful bargaining chips and one of the most closely guarded assets of nuclear states, mistakes still can happen).
"Here we are in a world today where more countries have access to nuclear weapons than ever before," Mr Ford said, adding that when he left college in 1992 he thought the nuclear age had come to an end "and America would find ways to eliminate the number of chances that a rogue group or a rogue nation would get their hands on nuclear material".
"Today nine countries have it - more than ever before - and 40 are seeking it, including Argentina, Australia and South Africa," he said.
Mr Ford was referring to the nine known nuclear weapon states: the US, the UK, Russia, China, France, India, Pakistan, Israel and now North Korea.
He said this made the US less safe because "more countries have nuclear weapons today which means the possibility of nuclear weapons falling into the wrong hands has increased dramatically".
This is pretty much what the proponents of NPT are saying: "stop with profilation or soon everyone has them and then it's just a matter of time before someone uses one".
