The first half of the 20th century saw two events that influenced the nature of conflict to the present day. The effects of two World Wars inflamed passions and hopes of nationalists throughout the world, and severely damaged the legitimacy of the international order and governments.
Nationalism on the Rise :-
Nationalism intensified during the early 20th century throughout the world. It became an especially powerful force in the subject peoples of various colonial empires. Although dissent and resistance were common in many colonial possessions, and sometimes resulted in open warfare, nationalist identities became a focal point for these actions.
Gradually, as nations became closely tied to concepts of race and ethnicity, international political developments began to support such concepts. Members of ethnic groups whose states had been absorbed by others or had ceased to exist as separate nations saw opportunities to realize nationalist ambitions. Several of these groups chose terror as a method to conduct their struggle and make their situation known to world powers they hoped would be sympathetic. In Europe, both the Irish and the Macedonians had existing terrorist campaigns as part of their ongoing struggle for independence, but had to initiate bloody uprisings to further their cause. The Irish were partially successful, the Macedonians failed.
The "total war" practices of all combatants of WWII provided further justification for the "everybody does it" view of the use of terror and violations of the law of war. The desensitization of people and communities to violence that started in World War I accelerated during World War II. The intensity of the conflict between starkly opposed ideologies led to excesses on the part of all participants. New weapons and strategies that targeted the enemies' civilian population to destroy their economic capacity for conflict exposed virtually every civilian to the hazards of combatants. The major powers' support of partisan and resistance organizations using terrorist tactics was viewed as an acceptance of their legitimacy. It seemed that civilians had become legitimate targets, despite any rules forbidding it.
Cold War Developments :-
The bi-polar world of the Cold War changed perception of conflicts the world over. Relatively minor confrontations took on significance as arenas where the superpowers could compete without risking escalation to full nuclear war. Warfare between the East and the West took place on the peripheries, and was limited in scope to prevent escalation. During the immediate postwar period, terrorism was more of a tactical choice by leaders of nationalist insurgencies and revolutions. Successful campaigns for independence from colonial rule occurred throughout the world, and many employed terrorism as a supporting tactic. When terrorism was used, it was used within the framework of larger movements, and coordinated with political, social, and military action. Even when terrorism came to dominate the other aspects of a nationalist struggle, such as the Palestinian campaign against Israel, it was (and is) combined with other activities. Throughout the Cold War, the Soviet Union provided direct and indirect assistance to revolutionary movements around the world. Many anti-colonial movements found the revolutionary extremism of communism attractive. Leaders of these "wars of national liberation" saw the advantage of free weapons and training. They also realized that the assistance and patronage of the Eastern Bloc meant increased international legitimacy. Many of these organizations and individuals utilized terrorism in support of their political and military objectives. The policy of the Soviet Union to support revolutionary struggles everywhere, and to export revolution to non-communist countries, provided extremists willing to employ violence and terror as the means to realize their ambitions.
The Internationalization of Terror:-
The age of modern terrorism might be said to have begun in 1968 when the Popular Front for the Liberation of Palestine (PFLP) hijacked an El Al airliner en route from Tel Aviv to Rome. While hijackings of airliners had occurred before, this was the first time that the nationality of the carrier (Israeli) and its symbolic value was a specific operational aim. Also a first was the deliberate use of the passengers as hostages for demands made publicly against the Israeli government. The combination of these unique events, added to the international scope of the operation, gained significant media attention. The founder of PFLP, Dr. George Habash observed that the level of coverage was tremendously greater than battles with Israeli soldiers in their previous area of operations. "At least the world is talking about us now." Another aspect of this internationalization is the cooperation between extremist organizations in conducting terrorist operations. Cooperative training between Palestinian groups and European radicals started as early as 1970, and joint operations between the PFLP and the Japanese Red Army (JRA) began in 1974. Since then international terrorist cooperation in training, operations, and support has continued to grow, and continues to this day. Motives range from the ideological, such as the 1980s alliance of the Western European Marxist-oriented groups, to financial, as when the IRA exported its expertise in bomb making as far afield as Colombia
Current State of Terrorism :-
The largest act of international terrorism occured on September 11, 2001 in a set of co-ordinated attacks on the United States of America where Islamic terrorists hijacked civilian airliners and used them to attack the World Trade Center towers in New York City and the Pentagon in Washington, DC. Other major terrorist attacks have also occured in New Delhi (Indian Parliament attacked); Bali car bomb attack; London subway bombings; Madrid train bombings and the most recent attacks in Mumbai (hotels, train station and a Jewish outreach center). The operational and strategic epicenter of Islamic terrorism is now mostly centred in Pakistan and Afghanistan.