The Latest: Trump's Long-threatened Tariffs Against Canada And Mexico Go Into Effect

President Donald Trump's long-threatened tariffs against Canada and Mexico went into effect Tuesday, putting global markets on edge and setting up costly retaliations by the United States' North American allies.

Also, Trump will stand before a joint session of Congress on Tuesday to give an accounting of his turbulent first weeks in office as a divided nation struggles to keep pace, with some Americans fearing for the country's future while others are cheering him on.

Here's the latest:

China defended its efforts to control the flow of fentanyl to the US

That came as new American tariffs took effect Tuesday on Chinese imports.