By Keith Doucette Premiers in the Atlantic region say that despite Canada being left out of the latest round of global U.S. tariffs, they need to hold the line in the face of growing economic uncertainty. On Wednesday, U.S. President Donald Trump announced a 10 per cent baseline tariff on imports from most countries, but a White House fact sheet said goods covered by the free-trade deal between Canada, the U.S. and Mexico were exempted. Trump also said he is going ahead with previously announced 25 per cent tariffs on automobile imports starting Thursday, which will add to existing 25 per cent tariffs on Canadian steel and aluminum. In a statement released late Wednesday, Nova Scotia Premier Tim Houston said Canada may have been spared the worst-case scenario, but thousands…