The threat of the domino effect pertains to US control of "vital" strategic and natural resources within it's dependencies such as in Venezuela before Chavez. So for example, during the U.S. terrorist wars in Central America, Thomas O. Enders, an Assistant Secretary of State, warned a House subcommittee: In a 2004 report forecasting U.S. hegemony in Latin America, the U.S. National Intelligence Council, an advisory group to the CIA, National Security Council (NSC) and Pentagon made up of military and academic national security experts, warned that U.S. corporate and power interests would be threatened by "a wave of anti-imperialistic governments" and "radical, politically revolutionary movements" which would have "a demonstration or contagion effect [which] could cause spillover into other nations.":
And then the world would be "mobilized against you as a butcher" as National Security Adviser Henry Kissinger warned Nixon as he was advocating dropping a nuclear bomb on North Vietnam: National Security Archive: Nixon White House Considered Nuclear Options Against North Vietnam, Declassified Documents Reveal