What does domestics tranquility?

Answer 1

"The United States Constitution states right at the beginning that one of the reasons for its creation was to establish a government which could provide for the "Domestic Tranquility." This is ultimately an ambiguous concept and can mean any number of things, but in the context of the creation of the Constitution, it referred largely to the idea that a federal government should be powerful enough and have the authority to quell rebellions and prevent violent conflict between lower levels of governments, such as between the states."