Preemptive war (or a preemptive strike) is wage in an attempt to repel or defeat a perceived inevitable offensive or invasion, or to gain a strategic advantage in an impending (allegedly unavoidable) war. Preemptive war is often confused with the term preventive war. While the latter is generally considered to violate international law, and to fall short of the requirements of a just war, preemptive wars are more often argued to be justified or justifiable.