This is actually an incredible story.
The law in question is the Sheppard-Towner, signed into law in November, 1921.
This law was the very first law at the Federal level ever passed to provide some help to those in need. It is also of interest that the law was the first major piece of Federal legislation passed after women got the right to vote. The author was female and the first to introduce it to Congress was female. The idea grew out of the work of Josephine Baker in NYC and it was one of her colleagues who first wrote it.
The law allocated funding to establish maternal-child health centers and services related to such. This included topics such as hygiene, nutrition, and services such as visits and literature.
The Congress passed it with overwhelming majorities and Harding supported it and signed it. But this was all in spite of vigorous opposition from the AMA which feared public health would kill the private medical business.
The law needed renewal, but by 1929 the power of the opposition from the AMA, as well as women opposed to women voting, and other reactionary forces, Congress failed to continue its funding and it lapsed.
Now, prior to 1930, all pediatricians who wanted to be in organized professional society, joined the AMA. Pediatric issues were voted on in the Pediatric Section of the AMA House of Delegates. That section voted in 1929 to support renewal of the Sheppard-Towner Act. The full AMA House of Delegates was outraged that a section would cross a fiercely held position. Those pediatricians who stuck to the principal that children come first, bolted out of the AMA, forming the AAP in 1929, with official founding to take place in 1930.
The development of Sheppard-Towner, that is Federal laws, to promote public health grew out of many pediatrician's work such as L. Emmet Holt in founding a scientific approach to good, clean nutrition, decreasing infant mortality, etc. Then came along the Children's Bureaus, out of which came Sheppard-Towner.
I have always loved this part of the AAP founding story. If you think about the whole story, from L. Emmet Holt right through the founding of the AAP, we were the only part of the profession of medicine that not only accepted the idea of working with women, but collaborated enthusiastically and fully. It was women who led the way in the Children's Bureau movement, and the male pediatricians linked arms with this movement. They helped create the science that served as the foundation, and then worked hard to support the application of their science in the Bureau's.
It is also striking that pediatricians founded the AAP, in part, as a response to the AMA's choice to pick the welfare of doctors over the well-being of the families they serve. The pediatricians who walked out of the AMA did so in protest to the AMA opposition to the Sheppard-Towner Act, and in support of the maternal and child health promotion it funded. The AAP was founded to help families, not pediatricians, and I find that most admirable and exceptional in the annals of American medicine.
This is a detailed account rich with detail on the early role of pediatricians in the 1880's (Holt and others), and then the story of the founding of the AAP around this Act.