But now, ahead of 3D theatre re-release of T2 next month, Cameron says he is in negotiations to oversee a new "three-film arc" if the ongoing issues with the rights to the franchise can be resolved. The rights to make the films have changed several times since the release of the first film, but under US copyright law some rights will revert to Cameron in 2019. Schwarzenegger would be involved "to some extent" in the proposed trilogy but the plan would be to introduce new characters to "pass the baton".
"The question is - has the franchise run its course or can it be freshened up?," says Cameron. "Can it still have relevance now where so much of our world is catching up to what was science fiction in the first two films. We live in a world of predator drones and surveillance and big data and emergent AI (artificial intelligence).
"So I am in discussions with David Ellison, who is the current rights holder globally for the Terminator franchise and the rights in the US market revert to me under US copyright law in a year and a half so he and I are talking about what we can do. Right now we are leaning toward doing a three-film arc and reinventing it."
"We'll put more meat on the bones if we get past the next couple of hurdles as and when we announce that."
Cameron has been circumspect about the films made since his departure, Rise Of the Machines (2003), Salvation (2009) and Genisys, but has tempered his criticism out of respect for his long-time friend Schwarzenegger, who has appeared in all of them.
"I think it's fairly widely known that I don't have a lot of respect for the films that were made later," Cameron says. "I was supportive at the time in each case for Arnold's sake because he is a close friend. He has been a mate of mine since 33 years ago so I was always supportive and never too negative. But they didn't work for me for various reasons."
Cameron is about to start shooting the first of four long-awaited sequels to Avatar, which will be released in December 2020. A passionate environmentalist and underwater explorer - he became just the third person to reach the deepest part of the ocean in 2012 - Cameron says the sequels will reflect the environmental themes of the first film, but not at the expense of the story.
"I think the critical balance to be struck in the sequels is to make sure that it doesn't thematically overwhelm the entertainment value. And it won't," he says. "If you have great characters and great visuals and great settings and a powerful story, which I believe we do, then the thematic stuff can continue at about the same level as in the first film and to me then it's a positive resonance.
"I think people will expect the Avatar sequels to do what the first one did, which is to appeal to them at different levels, including even a spiritual level and hopefully that will all be there for them. I can't become more didactic and start banging people over the head with something that a lot of them don't want to hear about. I'd rather do that in my non-Avatar activism and philanthropy and investment in which I am very active in trying to reinvent our perception of food and agriculture."
