GEOFF BENNETT: Welcome to the "News Hour."

Canadian Prime Minister Mark Carney says Canada will move quickly to reduce its economic reliance on the U.S., as retaliatory tariffs take effect on roughly $20 billion worth of American goods.

AMNA NAWAZ: The tariffs, some as high as 50 percent, match duties President Donald Trump imposed on Canadian imports earlier this year.

The latest escalation follows months of strained relations and unsuccessful trade negotiations between the two countries.

And, for Canada, today's confrontation marks a turning point with its much larger neighbor.

MARK CARNEY, Canadian Prime Minister: They were asking far too much and offering far too little.

AMNA NAWAZ: Just after midnight last night, one of America's closest allies struck back.

MARK CARNEY: Since a fair deal wasn't on the table, we made the right choice to walk away from a bad one.

AMNA NAWAZ: Canada imposing new tariffs on roughly $20 billion worth of U.S.

goods, targeting hundreds of products from steel and aluminum to clothing and cheese.

These retaliatory tariffs come after months of building pressure by the U.S.

KAROLINE LEAVITT, Former White House Press Secretary: The tariffs are incoming tomorrow on Canada.

AMNA NAWAZ: In February of last year, President Trump announced sweeping 25 percent tariffs on many Canadian goods.

DONALD TRUMP, President of the United States: They need us to survive.

AMNA NAWAZ: In July, he announced new 50 percent tariffs targeting roughly $20 billion in Canadian products, including wine, dairy, clothing and hockey equipment.

Those went into effect in late August.

The latest escalation from Canada follows failed trade talks, months of private negotiations between the neighboring countries, and an ongoing public pressure campaign by President Trump, from renaming Lake Ontario Lake America... DONALD TRUMP: And all it takes is a good pen and some intelligence.

AMNA NAWAZ: ... to repeatedly suggesting Canada should become the 51st U.S.

state.

Over the weekend, the president posted this A.I.-generated cartoon depicting him looming over Carney with a hockey stick and calling the prime minister governor.

Just yesterday, Trump threatened to block Canadian plane maker Bombardier from selling jets in the U.S.

unless it moves production to American soil.

"That era is over," the president wrote.

"If they want our market, they must build here and stop treating America like a piggy bank."

While the tariffs only affect about 5 to 6 percent of total goods each country imports from the other, larger uncertainties in this new era of U.S.-Canada relations remain.