Mobilization came during World War II, when the US military eyed the open land and easy access to the Gulf of Mexico. With no use for muskrat, the Department of Defense built a massive factory to produce C-46 cargo planes and military tank engines. After the war, as America sought to assert its superiority in space, NASA took control of the Michoud Assembly Facility and its cavernous interior to manufacture the mighty Saturn rockets that would deliver a dozen Americans to the Moon. NASA famously built its space shuttle external tanks here—more than 130 of them.

Today, NASA still builds in Michoud, assembling the core stage of its massive Space Launch System rocket. But unlike the Cold War-era race to the Moon or the space shuttle heyday, Michoud no longer has exclusive domain over US rocketry. Private competitors are building them faster and cheaper in places like Decatur, Alabama; Hawthorne, California; and Kent, Washington.