President Trump signed a proclamation this afternoon establishing tariffs on imported steel and aluminum over the objection of many Republicans in Congress and the U.S. business community, excluding steel companies. Canada, the largest exporter of steel to the U.S., and Mexico will be temporarily excluded from the new tariffs pending conclusion of the NAFTA renegotiations. President Trump will retain authority to change the level of tariffs on individual countries in the future. Overnight futures trade was mostly lower ahead of the midday release of the March WASDE. Some of the selling was due to hints from weather models of a more significant rainfall for Argentine crop areas in the 18-30 March period. How much good such rains this late m...