Very briefly, I am firmly in the camp that this is a bag idea. The process by which it is being formed is atrocious. On substance, I think a number of left-leaning voices raise great points - how is this thing a good deal, overall, for the American people?
If you believe in the unassailable magic of the theory of free trade, you won't have a facial issue with it. But in the details, there is a Devil.
Some argue that this agreement will help form a bulwark against a looming and menacing China - I don't necessarily agree with that, but I have a more troubling question: why are we worried about China? Wasn't our robust free trade experiment with China supposed to turn that country into an ally with interdependent economic interests and would transform China into a liberal state we could count on? Now you're telling me that China is a worrisome potential belligerent?
So, let me get this right - we opened our markets, let China get vastly richer as a result, and now we don't simply face an aggressive totalitarian state, but an aggressive totalitarian state that is vastly better armed as a result of our policy?
Perhaps we need to be wary of this whole concept.