Donald Trump might be the first American to pick a fight with a Canadian in the history of the world.

After the G-7 meetings over the weekend, where Canadian Prime Minister Justin Trudeau said he found Trump’s trade posture toward Canada “insulting,” Trump tweeted Sunday that Trudeau was “very dishonest & weak.” Larry Kudlow, the president’s economic adviser, finished the pile-on by accusing Trudeau of “betrayal,” while Trump’s new trade adviser, Peter Navarro, said later on Fox News Sunday that Trudeau is a back-stabber who “engaged in bad faith” and deserves a special place in hell.

All of this for the leader of a country that peacefully shares the United States’ largest border and has been so loyal in foreign affairs that Canada is nearly synonymous with the U.S. in conversations about Western democracies. Most important, Canada is tied with China as the United States’ largest trading partner, which makes it a key player in our economic health and crucial to our continued success.

As the Trump administration came out swinging, the response from congressional leaders was … total silence. If they were worried by the president’s attacks on one of our closest allies, they didn’t make it known publicly.

Watch: Ryan — Reining In Tariffs Requires Passing a Bill the President Would Sign Into Law

A real drag

It’s the same posture GOP leaders adopted toward massive global tariffs that the president has threatened, abandoned and now returned to again. But unlike the tweets and insults for Trudeau, which are just embarrassing, the tariffs on goods from Canada, Mexico, China and other trading partners could drag down the economy that Trump and Republicans have taken pains to pump up with tax cuts and cheer on from the sidelines. The damage to the U.S. from a trade war with Canada and other partners could be real and lasting.

That’s the anxiety you could see this weekend in editorials across the country in states that voted for Trump and are represented by Republican leaders, and yet somehow could be facing huge losses in the coming months if Trump instigates a trade war and congressional Republicans do nothing to stop him.

“Where are you, Sen. Mitch McConnell?” asked the editorial board of Louisville’s Courier Journal in an editorial Monday. “Kentucky needs you.”

Kentucky produced more than 1.3 million vehicles last year, many of them for foreign automakers, and made 95 percent of the world’s bourbon. So it’s reasonable for locals there to worry about what will happen if the president starts a global trade war that can’t be stopped.

In response to the possibility of increased tariffs on Kentucky bourbon, appliances and tobacco, McConnell said Friday that he hopes Trump will pull back from his rhetoric. But the hopeful tone didn’t do much to calm fears locally.

“It’s time for action and mobilizing Congress to push back against the president, Sen. McConnell,” the Courier Journal’s editorial board urged.

So far, no push back.

In Speaker Paul Ryan’s home state of Wisconsin, which has a trade surplus with Mexico and Canada, worries over future tariffs on local dairy products, boats, cranberries and Harley-Davidson motorcycles led to similar calls for GOP action.

“Wisconsin’s congressional delegation and the rest of Congress should demand the president stop slapping tariffs on American imports, which will result in retaliatory fees on vital state exports,” the State Journal editorial board wrote. “It’s bad for business, consumers and the economy — and it must end.”

But nothing’s ended yet.

In California’s Central Valley, where Rep. Kevin McCarthy’s agriculture-heavy district is centered, local press reports warned over the weekend about the damage that could be caused to local farmers by a trade impasse. 

In Waterloo, Iowa, the Courier editorial board warned “Trade Issues Could Hurt Iowa,” while Iowa soybean farmers spoke about wanting access to Chinese markets for their crops, not a fight with the Chinese government over tariffs.

“We want to sell to China, Mexico, whoever,” an Iowa farmer told the New York Times. “We should be part of the solution, which is bringing down the trade imbalance.”

In Michigan, where 38.9 percent of the state’s economy is tied to trade, auto part supplier Mary Buchzeiger told the Detroit Free Press, “Somebody is going to eat the costs of this action, and it’s ultimately going to be the American people. The very people who voted for President Trump will pay the ultimate price of these tariffs.”

In state after state, especially those the president won in 2016 (think Louisiana, Tennessee, South Carolina and Texas), the voices rising are people who otherwise support the president, but have deep anxieties about where all of this is heading and what effect it will have on their lives and businesses. For a man who swept into office by listening to people’s anxieties, Trump’s refusal to acknowledge them now is as discouraging as it is dangerous.

The test for GOP leaders now is to finally stand up to Trump for their states on trade after they’ve mostly looked past their disagreements with him on everything else. The standard line from Republicans since the president came into office has been that they’ll work with him when it’s good for their states and the country, and oppose him when it’s bad.

This is that moment, especially after the administration’s attacks on Trudeau over the weekend. If leaders won’t stand up to the president on trade now, when their own constituents could be so directly affected, it’s hard to believe they’ll ever stand up to him on anything in the future.