I believe there are significant disincentives for both sides to terminate, the way the agreement is structured.
For the U.S., with a 12-month standstill on termination, they would really not want to go to free trade, which this would imply, so there's a disincentive there.
For Canada, there is also a disincentive to terminate in that we don't have a standstill clause. If in fact we are in a situation where there are border taxes, it would not be to our advantage to terminate, because we would in fact find ourselves with almost automatically high anti-dumping rates. Both sides have serious reasons not to terminate.
The other reason I would give is both countries' governments--and only the governments can terminate this. I know I will sound naive, because everyone believes the coalition runs the U.S. government. The reality is that there's a huge amount of sweat equity on the part of both governments to resolve what has been a really sore issue for both of them over the last 20 years. Knowing that, I don't believe they would want to terminate unless they had really good reasons and something had gone radically wrong with the way it was working.