What Is the Theory of "Preemption" in Foreign Policy

What is the theory of "preemption" in foreign policy?

A) The United States reserves the right to "strike first" to prevent a punishing attack.
B) The United States reserves the right to use deadly violence against civilians to further a political goal.
C) The United States reserves the right to invade without any other supporters but only when the United Nations supports the action.
D) The United States must continue to have the largest military power in the world to preempt any other nation's interests.
E) The successful attempt of the United States to surpass Russia as the world's only superpower.