• President Trump's immigration policy is a threat to the economy.
  • Trump plans to greatly expand Border Patrol and immigration forces to deport more undocumented immigrants, who account for an estimated 3 percent of GDP.
  • This means job losses on scale not seen since the Great Recession.
  • Agriculture will take a particularly hard hit as an estimated 50 to 70 percent of farm workers are undocumented immigrants.
A file photo of Mexican agricultural workers on a farm in Holtville, Calif.

President Trump appears to have backed off of his plans to force funding for his Mexican border wall into the current budget but he's still seeking $314 million to add hundreds more Border Patrol agents and Immigration and Customs Enforcement officers.

Creating a deportation force of this magnitude could cost our economy $5 trillion over a 10-year period, according to a study by Queens College professor, Francesc Ortega.

The study assumes our labor force includes 7 million undocumented workers who account for 3 percent of our GDP; deporting millions of undocumented immigrants would create job losses not seen since the Great Recession.

And do you know the industry that would likely be most affected? Agriculture – the very industry Trump and Commerce Secretary Wilbur Ross have been defending recently. An estimated 50 percent to 70 percent of farm workers are undocumented.

Some farm workers are already starting to leave the country for fear of being deported. But, if farmers lost all access to undocumented workers it could cause agricultural output to plunge by $30 billion to $60 billion and it could force food prices higher by 5 percent to 7 percent, according to a study by the by the American Farm Bureau Federation (AFBF).

A big lie used by anti-immigration supporters is that immigrants take jobs away from native-born Americans, but the numbers do not agree when it comes to farming. Even when farmers raise wages, many say they don't get more than a few Americans applying for their jobs. And, even when an American applies and accepts a job — many don't come back the second day. It's hard, back-breaking work and it's seasonal and migratory — something most Americans don't want to do.

Our country needs more immigrants, not a deportation force or a border wall. Even if Trump wasn't cracking down on immigrants, the U.S. labor force is undergoing a massive shift as baby boomers retire. It's been estimated that close to 59 million workers will have left the workforce between 2010-2030, with only 51 million native born workers (third generation or higher) entering the labor force. Unless immigrants and children of immigrants enter the labor force in all industries, we will have a labor gap that will prevent us from creating the output we need and generating the growth necessary to keep America great.

Instead of wasting taxpayer's time and money with talks of a wall and a deportation force, our government should be focused on creating an immigration system that legalizes undocumented workers, and welcomes new, hardworking immigrants into our society and labor force.

Commentary by Julissa Arce is author of the book, "My (Underground) American Dream." Arce made national and international headlines when she revealed that she had achieved the American Dream of wealth and status working her way up to vice president at Goldman Sachs by age 27 while being an undocumented immigrant from Mexico. She currently works with the Ascend Educational Fund, a scholarship program for immigrant students in New York City. Follow her on Twitter @julissaarce.

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