Trucks cross the Ambassador Bridge between Windsor, Ontario, and Detroit on Feb. 10, 2017. (Paul Sancya/AP)

A Canadian public school board is temporarily banning student travel into the United States, citing an uncertain political climate resulting from President Trump's now-frozen executive order on immigration.

The Greater Essex County District School Board of Windsor, Ontario, has canceled field trips to the United States through at least February, as first reported by the Windsor Star.

“Paramount for us is student safety,” Clara Howitt, a school board superintendent, told the newspaper. “We really don’t know what will happen to our students at the border.”

Windsor is only about two miles from Detroit, directly across the Detroit River in Ontario, about 230 miles southwest of Toronto. The Canadian city is so close to the border that it's a mere 10-minute drive north (yes, north) into the United States. Its proximity means it's not unusual for students in Windsor to take “international” field trips to attractions in Michigan.

Howitt told the Detroit Free Press that canceled trips included one to watch “The Lion King” at the Detroit Opera House and to the Holocaust Memorial Center in Farmington Hills, Mich.

Trump signed orders Jan. 27 not only to suspend admission of all refugees into the United States for 120 days but also to implement “new vetting measures” to screen out “radical Islamic terrorists.” Refugee entry from Syria, however, would be suspended indefinitely, and all travel from Syria and six other nations — Iran, Iraq, Libya, Somalia, Sudan and Yemen — would be suspended for 90 days.

Trump's executive order sparked massive protests at airports across the country as reports surfaced that dozens of travelers from the affected countries, including green-card holders and dual nationals, were being detained. The rollout of — and fallout from — the ban continued to be chaotic: About a week later, a federal judge in Washington state issued a ruling that temporarily blocked enforcement of Trump’s controversial ban. The State Department then said it would reverse the revocation of visas under Trump’s executive order, allowing previously banned travelers to enter the United States.

On Feb. 9, the U.S. Court of Appeals for the 9th Circuit ruled unanimously to keep the ban frozen. Trump has said he may write a “brand new” immigration order, though White House officials have not ruled out taking the case to the Supreme Court. The president has continued to periodically tweet in anger about the decision.

The unpredictability of what could happen next was a major factor in the Windsor school board's decision to cancel trips. Because of its diverse student population, Howitt told the Detroit Free Press it was possible that some of them could be detained at the border. That had happened before, she added, when the United States clamped down on border security after Sept. 11, 2001.

“It's just right now the uncertainty of whether all of our students would be able to cross,” she told the newspaper. “So having had that experience in the past, we are just demonstrating due diligence at this period of uncertainty.”

The district represents Windsor and Essex County, one of the most diverse areas in Canada. Based on Canadian census data, the district projects that more than a quarter of the county population will be foreign born by 2031.

The hesitancy to even cross the border for academic reasons is not unprecedented. Canadian Broadcasting Corp. News reported that some law students at the University of Windsor, who also take classes at the University of Detroit Mercy to have a degree valid in both countries, had briefly stopped crossing into the United States after Trump's executive order. Those students were Canadian citizens who also had citizenship in one of the seven restricted countries.

Brian Masse, a Canadian member of parliament who has been critical of Trump's executive order, on Sunday linked to an article about the school board's decision.

“The tip of this has just emerged,” he wrote on Facebook.

Masse told the Windsor Star that Trump had built “a virtual wall” between the United States and Canada, and that it was regrettable that one of the canceled trips had been to the Holocaust Memorial Center in Detroit.

“If ever there was a point in which the world needed to learn about racism and prejudice and the unspeakable truths that need to be spoken, [now is the time],” Masse told the Star.

The school board's decision also came days before Canadian Prime Minister Justin Trudeau was scheduled to visit Trump in Washington on Monday. Formally, the two were set to discuss free trade and women in the workplace, though it remained to be seen if the travel ban would come up.

Trudeau, who has been outspoken about the need to welcome more refugees, tweeted several times after Trump signed his executive order, signaling that he disagreed with it without specifically calling out Trump by name. One was simply a repost of a photo of Trudeau welcoming a young Syrian girl to Canada; the prime minister had gone to the airport to meet refugees as they landed in Toronto in December 2015, handing out winter coats.

In another post, Trudeau reaffirmed that Canada would not change its stance because of the actions of its neighbor to the south.

“To those fleeing persecution, terror & war, Canadians will welcome you, regardless of your faith,” he tweeted. “Diversity is our strength #WelcomeToCanada”

Following Trudeau's tweets, the Canadian government said it would grant temporarily residence permits to anyone stranded in the country because of Trump's executive order, the Globe and Mail reported.

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