On Friday, Trump threatened to shut down the U.S. southern border in an attempt to bully Congress into advancing anti-immigrant legislation like a border wall. But even though a border shut down would be ineffective in reducing the flow of migrants seeking asylum at the border, it could be catastrophic for border communities that rely heavily on trade with Mexico. Trump’s proposal would be a disaster for Arizona’s economy, and could cost thousands of jobs if business with Arizona’s largest trade partner is disrupted.

Trump wants to shut down the U.S. border with Mexico to stop people from coming into the country, but his plan doesn’t actually address the problem.

Politico: “Closing the border, it’s been noted widely, would do nothing to prevent migrants from seeking asylum at ports of entry or from attempting to cross the border illegally.”

Nevertheless, Trump’s staff doubled down on his plans this weekend.

Vice News: “By Sunday, the White House was doubling down on the president’s ultimatum. To start, senior adviser Kellyanne Conway told ‘Fox News Sunday’ that Trump’s threat ‘certainly isn’t a bluff… You can take the president seriously,’ she added. Over on ABC’s ‘This Week,’ White House acting Chief of Staff Mick Mulvaney said that ‘something dramatic’ would need to happen for his boss not to make good on his word this week.”

What is clear is that the economic cost of a border shut down could be catastrophic.

CNN: “A closure could pose a major threat to international commerce. Robert Perez, deputy commissioner for Customs and Border Protection, told CNN’s ‘Right Now with Brianna Keilar’ on Friday that the closure of ports of entry would have ‘pretty severe’ consequences. ‘It’s Customs and Border Protection at every port of entry. Nearly 400 million travelers a year, $2.3 billion worth of trade, nearly 30 million trucks, rail cars and cargo containers every year.’”

Washington Post: “Sealing the border with Mexico, America’s third-largest trading partner, would disrupt supply chains for major U.S. automakers, trigger swift price increases for grocery shoppers and invite lawsuits against the federal government, according to trade specialists and business executives. ‘First, you’d see prices rise incredibly fast. Then . . . we would see layoffs within a day or two,’ said Lance Jungmeyer, president of the Fresh Produce Association of the Americas in Nogales, Ariz. ‘This is not going to help border security.’”

Border states like Arizona rely heavily on trade with Mexico and would be disproportionately harmed by a border closing.

Vox: “Shutting down ports of entry would be an economic disaster. It would also disrupt the lives of border communities that rely on the flow of people between the US and Mexico — including the major cities of San Diego (and Tijuana) and El Paso (and Ciudad Juarez). Approximately $1.5 billion worth of commerce happens along the US-Mexico border every day.”

Arizona Republic: “Border communities such as Nogales, Arizona, depend on sales taxes paid by Mexican shoppers as a key source of revenue. They often are the first to feel the impact of a decline in retail trade, and also feel it more heavily that other areas of the state.”