The history of science policy in the United States begins with WWII. Prior to the second war, science wasn't a large issue within government. The only governmental institutions that existed to promote and regulate science was the Smithsonian Institution and the Department of Agriculture. Before the 1940s, all scientific promotion and regulation was handled by outside organizations, such as the National Academy of Science and the American Association for the Advancement of Science.
Then came World War Two. To promote the development of scientific capabilities, FDR issued an executive order creating the Office of Scientific Research and Development (OSRD). At its head was the pioneer of science policy and the first presidential advisor on science and technology, Vannevar Bush. Under his leadership and a practically limitless fund, the OSRD helped put together some of the first large, publicly supported scientific projects, including research on radar, weapons, early-warning detection systems, and, of course, the atomic bomb.
When the war was over it was declared that science had won the war. But Vannevar Bush did not want to end there. In an influential document, called Science, The Endless Frontier, he argued that the same ingenuity of science that won the war should and ought to be applied in peacetime, to improve our standard of living, ensure our prosperity, and garuntee our resilience against future threats.
So begins science policy, the effects of which have led directly into the environmental policies that are so important in preserving our world.