NAFTA seems like a stupid place to start the debate. I have issues with it -- it's had a negative impact on both business and environmental regulation, and as far as I'm concerned anything that spreads current US copyright policy is a bad thing -- but it's not nearly the nightmare that WTO is.
EDIT: Relating this back to the earlier conversation:
This run isn't about changing the country, it's about Nader whacking off while he stares into a a mirror longingly (metaphorically).
I think it's about proving that a third-party candidate can get votes.
...and it's going to prove otherwise.
I would argue that it's about trying to get the Democrats to acknowledge that the corporate manipulation of our political system is a very bad thing.
I would further argue, as Tom did in the quoted bit above, that Nader's dreaming and he's never going to get that to happen, that any conversation he attempts to have immediately becomes about him and not about his message.
But -- and here's the part where I tie these two things together -- I think Nader would argue that it's obviously working because Clinton and Obama BOTH decided to go after NAFTA within days of him announcing his candidacy.
Which I think has about as much validity as Bush claiming credit for the lack of attacks on US soil since 9/11, and this rock keeping tigers away, but hey, it's Democrats suggesting that "free" trade agreements are not inherently a good thing. And that's a step up, even though, as I've said, NAFTA is certainly not one of the more egregious agreements we're in right now.