and decongestion, which meant more internal dwelling space per person and more external area per dwelling unit.

The proposed tenement improvements were expensive and fiercely resisted by property owners. Opposition was overcome, as was to happen in succeeding waves of intervention, by recruiting as advocates the upper ranks of civic leaders plus an assortment of social reformers and, even then, the media. The impetus for Wave One was more than an appeal to humaneness and compassion. As would be true of subsequent waves, a decisive argument was that doing good for the poor was doing good for everyone. Better housing was an act of self-preservation; even the affluent were prey to tuberculosis. A second compelling argument, which was also to re-echo in later eras, was the threat to the social order. Environment shapes character and, likewise, poor housing conditions were believed to spawn degraded people without capacity to meet the obligations of citizenship. It was during Wave One that housing was first construed as a "merit good," distinguishable from other consumer goods and entitled to the public regard. Housing thus evolved from a commodity into a cause.

The second wave of federal intervention arrived during the Great Depression. Not everyone remembers that President Hoover, not Franklin Roosevelt, was its instigator. It was through his prompting that the Home Owners Loan Corporation was established to rescue distressed homeowners and mortgate lenders. The era of subsidy had begun, albeit tentatively and selectively. A year or two later, the advent of the New Deal brought with it the full breadth of Wave Two: new programs to address the deficiencies of the "one-third of a nation [that was] ill-housed." Wave Two is remembered for its public housing-cum-slum clearance for the poor, and Federal Housing Administration (fha) mortgage insurance for the middle class. fha mortgages were unsubsidized; indeed, their insurance premiums ultimately yielded dividends. But public housing required a substantial federal appropriation to underwrite capital costs and an agreement from municipalities to waive most of the property tax. The span of subsidy widened.

The third wave came soon after World War II, inspired by the imperative of rehousing the millions of returning veterans who were bent on marriage and family. The new programs were also meant to provide outlets for the accumulated wartime savings of other millions who had at last the means to satisfy deferred yearnings for homeownership. Wave Three was accompanied by an extraordinary residential building boom, with new starts reaching an all-time high of nearly 2 million units a year, a level never before achieved. Veterans and other upwardly mobile families were assisted without explicit subsidy, apart from negligible amounts applied to