“As terrorist attacks multiplied and public concern mounted, National Security Directive 138 was adopted [on April 3, 1984], announcing the policy of using force against terrorists and moving from ‘defense to offense.’ Secretary of State George Shultz warned terrorists that they would pay a price for further attacks on the United States and that America was prepared to take ‘preventive or preemptive actions’ against terrorists.”
– Yonah Alexander, ed., Combating Terrorism, Page 44