Trade was not such a controversial topic not so long ago. For most of the post-war era trade worked well for the US and for many other countries. A bipartisan consensus supported continuing trade liberalization as long as it was accompanied by full employment. However trade always had winners and losers as economies adjust to different costs of production among trading partners and over the last few decades the number of US workers losing from trade mounted and the losses spread across hard hit communities. For these and other reasons, trade has become so controversial that it is now a key pivot point in politics and elections in the US.