It will be a splendid sight. A great march for children that for many will recall the idealism of the early 1960s, when Jack Kennedy lived and the civil rights movement fired America. Scratch the surface though, and a different tale emerges: of ideological controversy, political hypocrisy, and social tragedy.
The assembly point is Arlington Cemetery where JFK is buried. They will march cross the Potomac river to the Lincoln Memorial, from whose steps 33 years ago Martin Luther King proclaimed: "I have a dream."
Satellites will beam proceedings across the USA. It should be the best of days for the worthiest of causes. But best of all, not a single politician has been invited to speak.
The ritual talk about protecting children, family values and "America's future" already studs this election season. And in the most basic sense, children unarguably are the country's future. But in the real list of priorities of both political parties, they come next to last.
Marian Wright Edelman, the CDF's president, is a formidable operator with 24-carat credentials as a Friend of Bill and Hillary. But even she has been powerless to prevent a Democratic President from flirting with welfare reform schemes that scrap protection for the children of parents who cannot meet the new requirements.
The Republicans in Congress would go much further, taking aim at publicly- funded programmes, ranging from school lunches and special help for the poorest children to grants for college students - all in the sacred names of old-fashioned values and a balanced budget.
The efforts are clothed in exhortations about "getting government off the people's back", about family, community, and a lost sense of discipline, spiced with the musings of Speaker Newt Gingrich about orphanages. In fact the savings will help pay for tax cuts, tilted toward the better off.
Children do not have the vote, old people do. And old people do vote, in greater numbers than any other group. They are moreover the fastest growing segment of an ageing population; their interests dominate the calculations of Messrs Clinton and Bob Dole alike. That is why programmes benefiting the elderly such as Medicare and Social Security are sacrosanct. Rash is the politician who tangles with the American Association of Retired Persons (AARP).
And amid the bickering and double-talk, the plight of children deepens. According to the fund, on any given day 2,260 American babies are born into poverty, 8,493 children are reported as abused or neglected and three die for that reason, 2,700 teenage girls become pregnant, and 15 children are killed by guns.
A pygmy in terms of money and votes compared to lobbies like tobacco, the AARP or the National Rifle Association, the fund must look elsewhere. Hence the summons to arms on the Potomac. Like the Million Man March of black Americans, it is a sign of America's current quest for social renewal, outside the structure of a broken political system. Ms Edelman calls it "a moral line in the political sand". America's poorer families are praying that it holds.