Federal Social Compact 

From the minority report of the Pennsylvania ratification assembly (December 1787):

"In short, consolidation pervades the whole constitution. It begins with an annunciation that such was the intention. The main pillars of the fabric correspond with it, and the concluding paragraph is a confirmation of it. The preamble begins with the words, "We the people of the United States," which is the style of a compact between individuals entering into a state of society, and not that of a confederation of states...."

St. George Tucker, Blackstone's Commentaries: With Notes of Refernce to The Constitution and Laws of the Federal Government of the United States; and the Commonwealth of Virginia, William Young Birch, and Abraham Small; Philadelphia, c 1803. "View of the Constitution of the United States, Section 1"

"The constitution of the United States of America, then, is an original, written, federal, and social compact, freely, voluntarily, and solemnly entered into by the several states of North-America, and ratified by the people thereof, respectively; whereby the several states, and the people thereof; respectively, have bound themselves to each other, and to the federal government of the United States; and by which the federal government is bound to the several states, and to every citizen of the United States...."