President Bill Clinton's speech at the Democratic National Convention in Philadelphia on Tuesday was a colorful biography of his spouse that detailed her accomplishments and the relationships that defined her professional and personal life. Twice, the former president mentioned Hillary Clinton's mentor, Marian Wright Edelman, who founded the Children's Defense Fund.

Yet Clinton omitted an important episode in his wife's relationship with Edelman.

The two fell out over legislation that the former president signed in 1996 overhauling the country's welfare system. Hillary Clinton also supported the reform, but Edelman opposed it. Edelman's husband, Peter Edelman, was working in the Clinton administration at the time and resigned in protest.

The legislation was among the most consequential of the Clinton administration's economic policies, effectively ending the welfare system as it existed at the time. To receive help in cash from the federal government, enrollees had to meet a number of strict new requirements designed to encourage work.

The bill was popular, and Clinton signed it because he thought that it would help poor Americans support themselves. The Edelmans and some other advocates for the poor, however, feared that many beneficiaries would not be able to satisfy the new requirements and would stop receiving the financial help they needed to get by.

Many recipients left the rolls after the law took effect. Some were able to find work in an improving economy, but others couldn't. The requirements for vocational training, community service or similar programs designed to help them find work might have proved too burdensome for those who also had to care for young children or sick relatives or who were disabled themselves.

Economists who have studied the reform have found evidence that the law did encourage work, at least among those who were able to hold down a job, and many believe the new rules reduced poverty on the whole.

Yet those who could not find work — those whose circumstances were the most desperate — received less help.

One recent study concluded that the number of American households living on less than $2 a day in cash — excluding other forms of assistance such as food stamps and Medicaid — has nearly tripled since welfare reform, to 1.6 million families.

Other analyses that consider the full range of benefits the poor receive from the government have also concluded that poverty has deepened for those who are poor, even if fewer people are poor overall.

Hillary Clinton stands by the welfare-reform law, although she does support some modifications, such as relaxing lifetime limits on the amount of time people can spend on the rolls. Welfare reform provided beneficiaries "the tools they needed to find work and take care of their families," her adviser Maya Harris said in a statement earlier this year.

Harris also cited separate legislation signed by President Clinton that expanded a tax credit available to poor working families. Economists believe this subsidy, known as the Earned Income Tax Credit, is one of the main reasons that so many more unmarried mothers went to work during the Clinton administration.

During Hillary Clinton's last presidential campaign in 2008, Marian Wright Edelman told an interviewer that she and the Clintons were "not friends in politics." They seem to have put their differences behind them now. Edelman appeared in a campaign spot for Clinton last year. "I think we’re all in a good place now," her husband, Peter Edelman, told The Washington Post.

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