This past week, I sat in a large conference room and listened to a university student talk about his efforts to get an education. I was to give a presentation on the economy later, but his speech seemed far more interesting than the one I would deliver. As the young man told of his struggle to complete an engineering degree and get a job—he had just one more year to go—my mind turned to a couple of things I had just read about the U.S. labor market.

First, there are some 6 million unfilled jobs awaiting qualified workers; we face something of a labor market crisis. Second, the number of days required to fill a vacant job had just hit 31, up from 26 days back before the Great Recession in 2006, and an all-time high since 2001. The student hoped to fill one of those jobs so that he could pay off the bank loans that covered his education expenses.

But there was a problem. It's called regime uncertainty—or maybe I should say tweet uncertainty. The federal program that allows the young man to attend college at his expense, Deferred Action for Childhood Arrivals, might be ended at a moment's notice.

Brought to the United States at age five by undocumented parents, the student was participating in the 2012 program that enables those covered to become temporarily "legal" to obtain work permits, drivers' licenses, and Social Security cards, and to find a job and go to school. They can do this for two years with a possibility for renewal. To be eligible, the young person has to be at least 15 with a high school degree.

Some 800,000 individuals now participate in the program, and the success rate expressed in terms of employment, earnings, and school completion is impressive.

Articulate and passionate about completing his education, the student stood before the audience I would address later and talked about the amazing opportunity he had been given. He told about holding multiple jobs, attending community colleges prior to entering his university, and finding individual business people who would co-sign loans with him to pay tuition. He was willing to pay the full sticker price—no in-state tuition or state or federal aid is available to him.

He was obviously creative, willing to work hard, and had a definiteness of purpose. He seemed to be just the kind of person we should welcome to our shores; an example of what the late economist Julian Simon called "the ultimate resource."

But why might DACA come to an end? Sure, there is some administrative cost, but those in the program receive no federal aid. No, it is not about budgets; it's about politics.

There are those who feel threatened by eager young people looking for work, and there are others who think in terms of zero-sum outcomes. As they see things, if someone succeeds, that means someone else fails. If one person gets a seat on the bus, someone else will have to await another bus. Yes, these and other concerns about undocumented workers were communicated strongly in the 2016 election.

But there are gains from trade and immigration. Our market economy prospers each time someone voluntarily fills one of those 6 million unfilled jobs. No one gains when employers are begging for workers, and can't find them because those willing to take the job are sidelined.

When someone takes a seat on this bus, it actually gets larger. Any person who is willing to pay the full price for an education and to work while doing so should be encouraged. No, better than that, they should be cheered. Indeed, they should be embraced and welcomed to the wonderful world of work.

It's past time, long past time, for Congress to come to grips with the undocumented worker problem, especially for those who were brought here as children and are now as American as they can be.

Bruce Yandle is a contributor to the Washington Examiner's Beltway Confidential blog. He is a distinguished Mercatus Center adjunct professor of economics at George Mason University and dean emeritus of the Clemson University College of Business & Behavioral Science. He developed the "Bootleggers and Baptists" political model.

If you would like to write an op-ed for the Washington Examiner, please read our guidelines on submissions here.