On the issues of labour rights and the environment, it strikes me as self-evident that we have a better capacity to influence countries on those issues if we have an economic relationship under a rules-based system. This has been proven repeatedly. Increased economic engagement helps to provide legitimate economic opportunity. In some cases, it has weaned countries off illicit activities that subordinate rights and threaten security.
There's no trade agreement that's perfect. But if a trade agreement puts labour and environmental issues on the table for an ongoing discussion and evaluation, isn't it an improvement over no agreement at all?