The study, published by researchers at Ball State University in Muncie, Indiana, warn these job losses could have significant impacts on households and families, causing those who may already be disadvantaged to be hit even harder.

“These studies reveal that roughly one in four American jobs, across the income and educational spectrum, are at risk of foreign competition in the coming years,’ the researchers explain.

The study also found that a disproportionate percentage of job growth and business expansion in recent years has occurred in only a small number of metropolitan areas.

"Half of net establishment growth [or business formation] in the United States … occurred in just 0.64 percent of the more than 3,100 US counties," the researchers estimate.

He repeatedly warned that he would impose an import tariff on goods made by American manufacturers that moved jobs offshore.