The Earth is getting hotter. How heat domes, El Niño and greenhouse gases all play a part.

WASHINGTON — The July 1 deadline came and went without a renewal of the Canada-U.S.-Mexico Agreement, as Washington opted instead for the annual review process . President Donald Trump wants to renegotiate the deal to address what he sees as persistent U.S. trade deficits with Canada and Mexico. To understand where CUSMA (aka USMCA) is headed and what it means for Canadian businesses and the U.S. states most exposed to cross-border trade, National Post spoke with trade policy and tariffs specialist Gary Clyde Hufbauer, who previously served with the U.S. Treasury Department, and is now...