Trump's erratic protectionist policies aren't helping the U.S. a bit.

Trump’s bizarre decision to further wage war with some of the U.S.’ closest allies (Canada!) has left our longtime partners stunned and angry. Meanwhile, America’s real trade foes, such as China, stand poised to benefit from Trump’s reckless policies.

French President Emmanuel Macron warned, “economic nationalism leads to war. This is exactly what happened in the 1930s.” In a phone conversation with Trump, Macron also stressed that his trade moves might be illegal.

Meanwhile, Canadian Prime Minister Justin Trudeau called the tariffs “totally unacceptable,” as Canada quickly announced plans to slap tariffs on $14 billion worth of U.S. products, from steel to toilet paper.

The Trump administration is rolling out the tariff under the banner of national security, which Trudeau openly mocked. “That Canada could be considered a national security threat to the United States is inconceivable,” he said.

Britain’s former trade minister Francis Maude added, “This is stupid. It’s counterproductive. Any government that embarks on a protectionist path inflicts the most damage on itself.”

In March, the administration announced import tariffs of 25 percent on steel and 10 percent on aluminum, with temporary exemptions initially extended to Canada, Mexico, and the European Union. Those exemptions expired this week.

Not only is Trump positioning the U.S. to be isolated from the world in terms of trade, but he finds himself isolated at home on the issue, as even Republicans and GOP-friendly business groups line up to blast his protectionist agenda, which will clearly lead to higher prices for U.S. consumers and is likely to be a jobs killer at home.

“The current approach will deliver the greatest economic pain to precisely those areas of the country that the administration and the Congressional majority are counting on for continued political support,” warned Tom Donahue, president and CEO of the business lobbying group Chamber of Commerce. “It is worth remembering that a tariff is nothing more than a tax, and it is not paid by the exporting country — it is paid by the American people.”

In other words, American beer drinkers will be paying more to purchase six-packs of aluminum cans.

On Thursday, Republican Senators also lashed out. Pat Toomey (R-Pa.) denounced Trump’s latest move as “bad news,” while the tariffs were dubbed “dumb” by Sen. Ben Sasse (R-NE).

A recent study by the Brookings Institute showed 12 of the 15 states likely to take the biggest tariff hits are red states that supported Trump.

Trump’s trade war is upsetting allies everywhere, at home and abroad.