The United States benefits from international trade, and Asia and the United States have a mutually beneficial and deepening economic relationship. A byproduct of that deepening economic integration, however, is a tendency toward increased income and wealth inequality within the United States. The appropriate response is not to adopt trade protection but rather implement a package of improved adjustment measures and longer-term policies to enhance US competitiveness.
The rejection of TPP was, to borrow a sports term, an own goal that damaged US interests and further opened the door for Chinese leadership. The United States has a multifaceted economic relationship with China, and the issues of currency manipulation, NME status, and market access are all potential flashpoints. Mismanagement of these issues could harm the US economy and create collateral damage elsewhere in Asia. The pursuit of bilateral deals is likely to be difficult (because of the perception of their zero-sum nature) and have relatively limited impact. Rather than retreating or pursuing bilateralism, a re-examination, revision, and expansion of a regional agreement along the lines of TPP is more likely to generate substantial and sustained benefits to the US economy.
Unfortunately, the Trump administration is in effect doing the opposite: increasing contingent or process protection, which could significantly hurt some Asian partners, and demanding renegotiation of existing deals such as NAFTA and KORUS, threatening to terminate them if renegotiations are unsuccessful. There is scope for improvement of both agreements. But badly renegotiated deals could harm the US economy and disadvantage trade reliant partners in Asia. In the worst case, these actions could spark trade wars to the detriment of all.