It's secretive because politicians can't have discussions and make deals if everything they say is picked over by their constituents and enemies. While they ma

It's secretive because politicians can't have discussions and make deals if everything they say is picked over by their constituents and enemies. While they may end up at a trade deal that people want, they won't necessarily like how it ends up there. For example, there may be a version 0.5 of the document where New Zealand must give up their single-buyer drug plan (Pharmac). This is, I believe, FATAL to the treaty in New Zealand. However, the US demands that it is there. They've got several drug companies who are able to see the agreement and they want it in. It will be gone by 1.0, but to do that some horse trading needs to happen. So, everyone throws their wish list into the pot and then they negotiate to see what is on a requires list. Now imagine what would happen if all that happened in front of the voters. Imagine if the first thing that you heard about the agreement was that Pharmac (the drug buyer) was going to be made illegal, and your drug costs were going to go up by a factor of 10. Yeah, it'd be dead right out of the gate. New Zealand definitely doesn't want that, they want to ship food (milk solids) to the US. The US doesn't want that either... China has a free trade agreement with NZ, and since signing has become NZ's second largest export market, bigger than the US by 50%.