“Once we’re in a world with a MID,” says Todd Sinai, a professor of real estate and public policy at the University of Pennsylvania’s Wharton School, “it is very hard to get to a world without the MID.” That’s in part because the benefit helps to prop up home values. It’s impossible to say how much, but a widely cited 1996 study estimated that eliminating the MID and property-tax deductions would result in a 13 to 17 percent reduction in housing prices nationwide, though that estimate varies widely by region and more recent analyses have found smaller effects. The MID allows home buyers to collect more after-tax savings if they take on more mortgage debt, which incentivizes them to pay more for properties than they could have otherwise. By inflating home values, the MID benefits Americans who already own homes — and makes joining their ranks harder.

The owner-renter divide is as salient as any other in this nation, and this divide is a historical result of statecraft designed to protect and promote inequality. Ours was not always a nation of homeowners; the New Deal fashioned it so, particularly through the G.I. Bill of Rights. The G.I. Bill was enormous, consuming 15 percent of the federal budget in 1948, and remains unmatched by any other single social policy in the scope and depth of its provisions, which included things like college tuition benefits and small-business loans. The G.I. Bill brought a rollout of veterans’ mortgages, padded with modest interest rates and down payments waived for loans up to 30 years. Returning soldiers lined up and bought new homes by the millions. In the years immediately following World War II, veterans’ mortgages accounted for over 40 percent of all home loans.

But both in its design and its application, the G.I. Bill excluded a large number of citizens. To get the New Deal through Congress, Franklin Roosevelt needed to appease the Southern arm of the Democratic Party. So he acquiesced when Congress blocked many nonwhites, particularly African-Americans, from accessing his newly created ladders of opportunity. Farm work, housekeeping and other jobs disproportionately staffed by African-Americans were omitted from programs like Social Security and unemployment insurance. Local Veterans Affairs centers and other entities loyal to Jim Crow did their parts as well, systematically denying nonwhite veterans access to the G.I. Bill. If those veterans got past the V.A., they still had to contend with the banks, which denied loan applications in nonwhite neighborhoods because the Federal Housing Administration refused to insure mortgages there. From 1934 to 1968, the official F.H.A. policy of redlining made homeownership virtually impossible in black communities. “The consequences proved profound,” writes the historian Ira Katznelson in his perfectly titled book, “When Affirmative Action Was White.” “By 1984, when G.I. Bill mortgages had mainly matured, the median white household had a net worth of $39,135; the comparable figure for black households was only $3,397, or just 9 percent of white holdings. Most of this difference was accounted for by the absence of homeownership.”

This legacy has been passed down to subsequent generations. Today a majority of first-time home buyers get down-payment help from their parents; many of those parents pitch in by refinancing their own homes. As black homeowners, Asare and Jean-Charles are exceptions to the national trend: While most white families own a home, a majority of black and Latino families do not. Differences in homeownership rates remain the prime driver of the nation’s racial wealth gap. In 2011, the median white household had a net worth of $111,146, compared with $7,113 for the median black household and $8,348 for the median Hispanic household. If black and Hispanic families owned homes at rates similar to whites, the racial wealth gap would be reduced by almost a third.

Racial exclusion was Roosevelt’s first concession to pass the New Deal; his second, to avoid a tax revolt, was to rely on regressive and largely hidden payroll taxes to fund generous social-welfare programs. A result, the historian Michelmore observes, is that we “never asked ordinary taxpayers to pay for the economic security many soon came to expect as a matter of right.” In providing millions of middle-class families stealth benefits, the American government rendered itself invisible to those families, who soon came to see their success as wholly self-made. We forgot because we were not meant to remember.

Proponents of the mortgage-interest deduction often claim that the benefit is a big help to middle-class homeowners. Vincent Wisniewski Jr. is one of them. Wisniewski, 35 and white, with brown hair down to his shoulders, worked with Diaz at HomeStart, but as a program manager. He and his wife, Kelly Kristof, an emergency-room technician, make about $79,000 a year, roughly the median household income for families in the Boston metro area. They live with their 9-month-old son in a 985-square-foot condominium that Wisniewski bought three years ago for $190,000.

Set on a quiet street in Winthrop, a community hemmed in by Logan Airport on one side and the Atlantic on the other, the condo features two bedrooms, a square kitchen with white cupboards, a television room and “the quiet room,” with hanging plants, guitars mounted on the wall and a large bay window. From the small back patio, the ocean is close enough to smell. The mortgage and property-tax bills are about $915 a month, and the monthly condo fee is $368, which includes expensive flood insurance. Even counting utilities, Wisniewski and Kristof spend about 22 percent of their combined income on housing costs. With what’s left over, they buy items for their son, take vacations and enjoy local restaurants. “We definitely feel comfortable,” Wisniewski told me.