A continuing U.S. policy issue has been whether terrorism should be considered as a crime or a mode of war. The question is not merely one of a choice of words. The two are different concepts with entirely different operational implications. If terrorism is considered a criminal matter, the appropriate response is to gather evidence, correctly determine the culpability of the individual or individuals responsible for the incident, and then apprehend and bring the perpetrators to trial. This has been the primary approach taken by the United States, and it has received wide international acceptance. To enhance this approach, the United States extended the jurisdiction of American courts to cover all terrorist acts against U.S. citizens and facilities anywhere in the world, thereby giving the Federal Bureau of Investigation legislative authority to investigate terrorist crimes and apprehend terrorists anywhere. Although not all nations accept this assertion, a number of terrorists have been turned over to U.S. authorities for prosecution in the United States.
Public trials of terrorists keep terrorism firmly in the realm of crime, strip terrorists of their political pretensions, and allow the United States to make a public case against those terrorists still at large. Dealing with terrorism strictly as a criminal matter, however, presents a number of problems. Evidence is extremely difficult to gather in an international investigation where some countries might not cooperate, and apprehending individual terrorists is extremely difficult. Moreover, the criminal approach does not provide an entirely satisfactory answer to a continuing campaign of terrorism waged by a distant group, and it does not work against a state sponsor of terrorism.
If, on the other hand, terrorism is viewed as war, there is less concern with individual culpability; only proximate responsibility—for example, the correct identification of the terrorist group—need be established. Evidence does not have to be of courtroom quality; intelligence reporting will suffice. The focus is not on the accused individual but on the correct identification of the enemy.
The United States has at different times taken both approaches, and recently began to orchestrate the criminal and military approaches, combining conventional evidence gathering and intelligence reporting to indict and prosecute terrorists, then combining that with information gained at trial to support further indictments, which were then utilized to justify military action.