Markets previously brushed off tariff risks under the assumption that President Donald Trump would follow his earlier pattern and eventually retreat. That allowed stocks to reach new record-high territory,

Key Points The president has extended his tariff pause until Aug. 1.His administration also sent letters to many countries letting them know what their tariff rates will be on Aug. 1 -- and many of these rates are high.

Wall Street on Friday was poised for a negative open, with stock index futures down, as President Donald Trump slapped a 35% tariff on Canada and warned of further hikes if Ottawa retaliated. S&P 500 futures (SPX) -0.