[1] The existence of master military contingency plans (of which Rex 84 was a part), Operation Garden Plot and a similar earlier exercise, Lantern Spike, were originally revealed by journalist Ron Ridenhour, who summarized his findings in a 1975 article in CounterSpy magazine.
[2] Starting in 1981, the DoD and FEMA began a tradition of bi-annual joint exercises to test civil mobilization using the names Proud Saber and Rex 82.
In 1984, the scenario involved a US Army rehearsal of airlifting the entire 82nd Airborne Division (consisting of 15,000 troops) from Fort Bragg in North Carolina, under the cover of night and flying them to either El Salvador or Nicaragua as a simulated invasion to enforce a state of martial law.
The plan was first discovered by the Christic Institute in 1984 and first revealed in detail in a major daily newspaper by reporter Alfonso Chardy in the July 5, 1987 edition of the Miami Herald.
Possible reasons for such a roundup were reported to be widespread opposition to a U.S. military invasion abroad, such as if the United States were to directly invade Central America.
[3][4][5] To combat what the government perceived as "subversive activities", the plan also authorized the military to direct the movement of civilian populations at state and regional levels, according to Professor Diana Reynolds.
[12] Rex 84B's scenario of mass detention of US citizens and residents under an unrealistic pretext and without congressional debate is often cited by civil libertarians[13] opposing the militarization of police, and has also given rise to the FEMA camps conspiracy theory.
[14] In 2003, Congressman Jim McDermott cited Rex 84B in raising concerns about martial law in the United States as part of the Global War on Terror.