Defense Programs: the mission

Posted: February 7, 2013 - 6:05pm | Y-12 Report | Volume 9, Issue 2 | 2013

During the early days of World War II, fear that Germany would create and use an atomic bomb led the U.S. to secretly launch the Manhattan Project to build one first.

Enriched uranium and plutonium were the two fissionable materials investigated for use. An original Manhattan Project site, Y‑12 was given the defense programs mission to enrich uranium to the level needed for an atomic bomb. Y‑12 produced the enriched uranium for Little Boy, the first atomic bomb dropped as a weapon, on Hiroshima, Japan, in August 1945.

At the war's end, the future of Y‑12 and the sprawling complex of laboratories and manufacturing facilities created under the Manhattan Project was unknown.

The Cold war

Y‑12's post-war role became clear when the Union of Soviet Socialist Republics, a former ally, successfully tested its first nuclear weapon in 1949. The nuclear arms race was on.

Physicists at the national laboratories were focused on researching the properties of nuclear materials, designing new weapons and finding other peaceful uses for the materials. Another site was needed for the production of multiple weapon components.

Y‑12's Jack Case, who later became the plant's manager, was sent by the Atomic Energy Commission to Los Alamos Scientific Laboratory to determine what was needed for Y‑12 to produce uranium metal for weapon components. Case and other Y‑12 experts were confident Y‑12 could perform the work. Bill Wilcox, a Manhattan Project chemist and later Y‑12 technical director, believes that decision “started Y‑12 on its second era.” The site soon began building uranium components for all the nation's nuclear weapons and test devices.

Y‑12's reputation in materials science and manufacturing excellence grew steadily after World War II. Those factors and a can-do attitude led the site into other mission areas; however, Y‑12's primary reason for existing remained weapon component manufacture. The end of the Cold War in 1991 brought a new period of uncertainty but also additional mission opportunities for Y‑12.

What Price Victory

Y‑12's ability to produce large numbers of complex weapon components helped drive the USSR into economic and political dissolution, but the Cold War also witnessed the rise of other nuclear powers. How could Y‑12 best defend the nation in this new world?

Faced with potential nuclear-equipped enemies and growing evidence of proliferation, the U.S. evaluated its military needs and strategic goals to determine the composition of the stockpile and what would be required to ensure its continued safety, security and reliability.

Consolidating operations and missions across the nuclear weapons complex led to the closure of some facilities. Non–defense programs missions were pursued to exercise the weapons production capability. Some Y‑12 technologies and skills were shared with the private sector, as the knowledge gained from weapons work was used to address other research and development issues.

Howard Baker, former U.S. senator from Tennessee and ambassador to Japan, explained the reasoning behind the changes: “When you have that much talent, that many resources and that much ability, and they are federally owned and operated, it seemed a waste not to utilize the resources for other federal programs.”


Though no new weapons are being produced, Y‑12 still has a vital defense mission. The nation is committed to meeting weapon retirement and dismantlement obligations.

The weapons that do remain in the stockpile require maintenance to ensure their safety and viability. The weapon Life Extension Programs launched in the 1990s ensure an effective nuclear deterrent (see page 10).

Seventy years after ground was broken for Y‑12, the core mission holds. As certain aspects of that mission transform to meet emerging global needs, Y‑12 remains focused on defending the nation and making the world a safer place.