They plan and rehearse their attacks. The trainers teach measures to counter response actions and innovations. And as governments take action to counter terrorism, terrorist organizations often alter their tactics. The many existing terrorist organizations constitute a threat for both peacetime and wartime. The probability of terrorism and other acts of sabotage and subversion is heightened during periods of hostilities.
Terrorism can be a means for a nation to project power.
Terrorism may be used to exhaust or deplete another nation's will or the resources of its armed forces. Terrorism, when used to cause governments to react repressively, can foment feelings of hatred toward government leaders and institutions. The structure of most terrorist groups prevents intelligence sources from infiltrating. But it is known that terrorist cadres often carry out orders from higher level leaders. And the groups are often maintained by strong political support.