Read: The utter inadequacy of America’s efforts to desegregate schools

In no way do we quibble with Congress’s decision to set aside more for high-poverty schools under Title I. That money is essential. However, making integration little more than a rounding error in the nation’s education budget defies decades of research suggesting that socioeconomic and racial integration is one of the most effective strategies for improving outcomes for disadvantaged students.

In an important 2010 Century Foundation study of students in Montgomery County, Maryland, the researcher Heather Schwartz of the Rand Corporation looked at children whose families were randomly assigned to public-housing units in a way that allowed her to compare the relative impact of compensatory spending and integration strategies. Some students were assigned to public housing in relatively high-poverty areas where schools spent $2,000 extra per pupil for reduced class size in the early grades, better professional development for teachers, and other initiatives. Other students were part of a housing-integration program that allowed low-income students to live in middle-class neighborhoods and attend middle-class schools that spent less per pupil. Both approaches helped, but the outcomes for students in the integrated schools and neighborhoods were far better.

During the very brief period—roughly a decade—in which Congress and the federal courts did prioritize desegregation, the results were very encouraging. When Congress passed the 1964 Civil Rights Act, which outlawed racial discrimination, and the 1965 Elementary and Secondary Education Act, which provided federal funding to schools, the combination created an important leverage point: School districts that didn’t desegregate would be barred from receiving the new influx of federal funding. The federal pressure worked, particularly in the South, where schools saw sharp reductions in segregation. Black students’ test scores rose, and white students’ scores stayed high.

Read: New York City high schools’ endless segregation problem

In the face of white backlash against school desegregation, however, Congress and the courts lost their nerve. In the early 1970s, a bipartisan group of legislators—including then-Senator Joe Biden—voted to prohibit the use of federal funds for transportation to achieve integration. Richard Nixon appointed conservative Supreme Court justices who cut back on the possibility of urban-suburban desegregation plans. Starting in the 1980s, the Reagan administration and its successors put little pressure on schools to desegregate.

In the years since, efforts to integrate schools have also been hampered by segregation in the housing market. The federal government’s investment in addressing this problem, too, has been exceedingly modest. The 1990s Moving to Opportunity program, which allowed low-income families to move to higher-opportunity neighborhoods, was funded at just $70 million. It ran into trouble when Senator Barbara Mikulski, a Maryland Democrat, killed an expansion of the program due to resistance from suburban-Baltimore constituents.