President Donald Trump’s proposal to cut in half the number of legal immigrants coming to this country each year would do a disservice to the nation as a whole and to many states in particular. There’s good reason to believe that Minnesota would be among the most harmed.

That’s a conclusion we draw not from politics, but from demographics and economics. Minnesota is in the early years of a long-expected and long-lasting slowdown in workforce growth — a product in part of a decline in birthrates beginning in the mid-1960s. Already, businesses are struggling to expand because of a shortage of workers, the state Department of Employment and Economic Development reports. If businesses can’t find the workers they need here, they’re a relocation risk.

That problem is likely to become more severe in the 2020s, when — if current trends continue — the 18- to 64-year-old population in this state will barely grow at all.

For Minnesota to stay prosperous, those trends must change. Increasing the state’s influx of international immigrants isn’t the only trend line that Minnesota should be trying to bend. Improving industrial productivity and maximizing the potential of those currently underrepresented in the workforce are also important. But opening the state’s door wider to immigrants was deemed “paramount” by a December 2013 report from the Minnesota Demographic Center. A University of Minnesota study last year said that if Minnesota is to maintain its current labor force growth rate, it will need to increase the number of people who move to the state more than fourfold.

That makes this a terrible time to constrict the flow of immigrants. It’s why several leading business organizations have come together as the Minnesota Business Immigration Coalition to advocate for the kind of federal reform that would serve this state well. It would include a pathway to citizenship for undocumented immigrants who have no criminal record; an easier process for employers to legally hire immigrants; and enlargement of both permanent and temporary admissions of foreign-born people, with flexible limits that can respond to the needs of industries as the economy ebbs and flows.

Trump’s plan, which fortunately faces long odds in Congress, bows a bit in that policy direction by holding steady the number of immigrants admitted on the basis of their job skills — now about 140,000 a year. But it would slam shut the nation’s door for would-be immigrants seeking to reunite with family members as it cuts the total number of newcomers in half. It would do nothing to move undocumented immigrants of long standing out of the nation’s shadows or make it easier for employers to hire immigrants. And it would cut in half the number of refugees admitted each year, disrupting the work of a number of Minnesota-based refugee resettlement organizations.

Trump justifies his proposal with a claim that American workers will do better with fewer immigrants. Minnesotans need to know that in this state, just the opposite is true. Reducing the number of immigrants would put a lot of jobs at risk.