Debates over immigration policy have assumed center stage in Washington and have even contributed to a government shutdown. President Donald Trump and his conservative allies want to put an end to “chain migration” that he says allows “truly evil” people into the United States. Unfortunately, Trump has tainted his proposals with racist outbursts that suggest his policy is designed to keep out more than terrorists and gang members. Democrats counter that immigrants have come to America as family units since the founding of the Republic. Both sides have hunkered down, convinced of their own righteousness and certain that history is on their side.

Few, however, know that the emphasis on family unification was the product of a legislative compromise between President Lyndon Johnson and an obscure Ohio congressman, Michael Feighan. It resulted from political expediency, not careful analysis, and it now stands as a prime example of how immigration policy today is the product of unintended consequences.

Since the 1920s, the national origins clause had served as the centerpiece of U.S. immigration policy. Under the system, the government allocated visas to nations in ratios determined by the number of persons in the United States in 1920. Since most of the people living in the U.S. at that time had roots in Northern and Western Europe, the clause effectively curtailed new waves of immigrants from Southern and Eastern Europe, Asia, Africa and Latin America. Europe consumed 98 percent of the quota, leaving only 2 percent for the rest of the world. Three countries—Ireland, Great Britain, and Germany—accounted for nearly 70 percent of the total. The quota did not apply to spouses or minor children of U.S. citizens or to residents of the Western Hemisphere, who could emigrate without restriction.

In 1963, President John F. Kennedy, a proud descendant of Irish immigrants, submitted a new immigration plan to Congress. The centerpiece of his legislation was a phaseout of the national origins provision over a five-year period. In its place, Kennedy proposed that immigrants from outside the Western Hemisphere apply on a “first-come, first-served” basis within specific preference categories. Half of the visas would be allotted based on skill or talent; 30 percent were reserved for the unmarried sons and daughters over the age of 21 of U.S. citizens, and 20 percent for spouses and unmarried children of immigrants admitted for permanent residence.

After Kennedy’s assassination, Lyndon Johnson took control of pushing the legislation through Congress. If JFK’s reforms were to have any chance of passing, they would need the support of Feighan, who served as head of the powerful House Immigration subcommittee. ...