President Donald Trump wants to change United States immigration policyby tying admission to job skills.In his recent speech to Congress,Trump said changing the way America decides who can immigrate can help the economy."It's a basic principle that those seeking to enter a countryought to be able to support themselves financially.Yet, in America, we do not enforce this rule,straining the very public resources that our poorest citizens rely upon."Trump said such a system is used successfully in Canada and Australia.Basing immigration on job skills is sometimes called a "merit-based" system.Under the current system, immigrants are taking jobs away from Americansby agreeing to work for lower pay, he said.It would be a major change in U.S. policy,which now gives a preference to spouses,children and parents of American citizens.In 2014, family-based immigrants made up 64 percentof all new legal permanent residents in the United States,reports the Migration Policy Institute.Marie Price, an immigration expert at George Washington University,said if the U.S. moves to a merit-based immigration system,it needs to do so carefully.She noted that in Canada admission is based largely on a point systemgiving higher scores to people with special skills and advanced degrees.But she said many of those admitted ended up driving taxis or delivering foodbecause they could not find jobs to meet their education skills.In some cases, professional licenses from other countries were not accepted in Canada.Since then, the point system has been changedso that people who can show they have job offers in Canada are given preference,said Sharyn Aiken of Queens University Law School in Canada.In addition, Canada looks at who can fill a range of jobs for which there are shortages of workers– such as child care, not just those requiring advanced college degrees, Aiken said.Senator Tom Cotton is a Republican from Arkansas.He has proposed a bill that would move the United States to the merit-based system proposed by Trump.His proposal would also reduce legal immigration by half-- from about one million a year to about 500,000.Under Cotton's bill, people with legal status in the U.S.could continue to get a preference for their children and spouses.But their parents will not get a preference.Cotton said many Americans believe the current immigration systemhelps businesses and not people."These Americans see cheap immigrant labor as a way to enrich the wealthywhile creating a near permanent underclassfor whom the American dream is always just out of reach," he said.William Stock is president of the American Immigration Lawyers Association.He disputes Cotton's argument that the U.S. is allowing too many immigrants into the United States.Stock said the U.S. admits about one million legal immigrants a year,a lower percentage of America's population than at any time in history.Stock also said it would be unfair to change to a merit based system for new immigrantswithout allowing those who have already applied for family members.He said some have been waiting 15 years or longer for a decision on their relatives.Stock added people calling for a merit-based immigration systemshould know that a promise of better wages in Americawill be not enough to get people to fill job openings in America.Many people will not want to move to the United States without their families-- making continuation of a family preference system important, he said.Trump has also followed through with his campaign promises of extreme vetting for immigrantsand of building a wall along the U.S. southern border with Mexico.