ISIS’s serial beheadings and recent enkindling of a Jordanian air force pilot have generated worldwide horror and opprobrium. But heinous and repugnant as these acts indisputably are, it’s important to recognize that terrorism is more calculated and choreographed than these mindless acts of barbarity suggest. Rather, these and other less egregious deeds are the products of strategic choices consciously made by terrorists to further their aims in order to attract attention to themselves and their causes.

Why terrorists persist in believing that the horror and havoc they create will eventually prove beneficial lies at the heart of understanding what drives them to inflict deliberately shocking, wanton violence on their opponents.

“A man who goes forth to take the life of another whom he does not know must believe one thing only—that by his act he will change the course of history.” Thus Itzhak Shamir, a future prime minister of Israel, explained the strategy of assassination that the Freedom Fighters for Israel—known to Jews by its Hebrew acronym, Lehi, and to the British, as the Stern Gang—embraced in the ’40s.

Although often denied, sometimes these acts can change the course of history.

Terrorism’s power to act as a fulminate for wider conflagration had already been demonstrated at the start of the 20th century by the assassin’s bullet that killed the Archduke Franz Ferdinand in June 1914 and set in motion the chain of events leading to World War I. And it was also evident after World War II when Palestinian terrorist attacks on Israel triggered the 1967 Six Day War. America’s invasions of Afghanistan and Iraq and the ongoing war on terror were of course prompted by the September 11, 2001 attacks. And the ISIS beheading of James Foley last September led to America’s re-engagement in Iraq.

Despite this history, terrorism’s role in galvanizing broader conflict remains mostly unrecognized today. Indeed, despite evidence to the contrary, we continue to explicitly deny terrorists’ ability to catalyze systemic change.

“Terrorists can never win outright,” Rhodesian Prime Minister Ian Smith confidently declared in 1977. Following the 1983 suicide truck bombing that killed 241 U.S. Marines in Lebanon, President Ronald Reagan defiantly proclaimed that “the main thing,” is to show that terrorism “doesn’t work… [and] to prove that terrorist acts are not going to drive us away.” Margaret Thatcher described the Irish Republican Army’s (IRA) attempt to kill her at the 1984 Conservative Party Conference as illustrative not only of a failed attack, but of a fundamentally futile strategy. And, in July 2006 Israeli Prime Minister Ehud Olmert promised that his government “will not give in to blackmail and will not negotiate with terrorists …”

Yet, Rhodesia is now Zimbabwe, the U.S. Marines soon departed Lebanon, Sinn Fein’s Martin McGuiness, a former PIRA terrorist, has been the Deputy First Minister of Northern Ireland since 2007, and that same year Olmert reversed himself and approved a deal with Hezbollah that freed five of its imprisoned terrorists in exchange for the bodies of two kidnapped Israeli sergeants. Hezbollah’s domination of Lebanese politics and the significant role it has played in the country’s government, including exercising effective veto power in the post-2008 national unity government, further challenges arguments about terrorism’s strategic futility. Indeed, neither Sinn Fein, the IRA’s long denied legal political wing, nor Hezbollah could ever have acquired the power, influence, and status they enjoy today if not for their terrorist antecedents.

One reason for terrorism’s historical intractability is the very understanding among various terrorist groups that terror can succeed as a strategy—provided its perpetrators learn from one another and thereby become capable of adapting and adjusting to even the most consequential governmental countermeasures.

Those terrorist groups that survive the onslaught directed against them by governments and their police, military, and intelligence and security services do so because they absorb and apply lessons learned from their predecessors. It may therefore surprise many readers to acknowledge that many of these lessons were first concentrated in the long struggle of Jewish militants during the ’40s who, despite their limited means, played a crucial role in creating the state of Israel by helping to drive out the British, who were frustrated by what we now understand as the first modern terrorist campaign.

Two Jewish militant groups—Lehi and the Irgun—fought the British during and after World War II in an attempt to end British rule of Palestine and evict what they perceived to be an occupation force preventing both Jewish autonomy and, more crucially at the time, Jews from escaping Hitler’s Europe.

Both groups intently studied the war of independence that resulted in Ireland’s freedom in 1922. Shamir’s underground nom de guerre in fact was “Michael” in reference to Michael Collins, the famed IRA commander. And both employed the same tactics of assassination, bombing, hostage taking, and extortion that have long been the staples of terrorists worldwide.

The Irgun had a particularly significant influence on terrorism’s future trajectory. The campaign launched by its commander, Menachem Begin, another future Israeli prime minister, in 1944 was arguably the first post-World War II war of national liberation to use spectacular acts of violence to attract international attention to themselves and their cause and thereby publicize the Zionists’ grievances against Britain and claims for statehood. These included the 1946 bombings of Jerusalem’s King David Hotel and the nearby Palestine Broadcasting Service’s studios, of the British Embassy in Rome, and a thwarted effort to mount a series of terrorist attacks in England as well.

In an era long before the advent of 24/7 news coverage and instantaneous satellite-transmitted broadcasts, the Irgun deliberately sought to appeal to a worldwide audience far beyond the immediate confines of their local struggle and beyond even the ruling regime’s own homeland—to include the United Nations and the U.S. as well.

The Irgun’s political front organizations in the U.S., for instance, were particularly successful in this respect: generating publicity and raising funds for the Irgun and securing the passage of resolutions by Congress condemning British oppression in Palestine and re-affirming American support for the establishment of a Jewish state. These activities presaged the efforts subsequently undertaken by Irish-American activists on behalf of Sinn Fein and the IRA, which had similarly corrosive effects on Anglo-American relations.

Lehi, however, always maintained that it was more discriminate in its operations than the Irgun. Moreover, compared to terrorist groups today, Lehi’s targets were not primarily civilians and its weapon of choice was often not the bomb that maimed and killed indiscriminately but the handgun pointed at the chest of the colonial officials and police officers charged with governing Palestine under the League of Nations mandate awarded to Britain after World War I. So precious were the group’s few weapons and so profound its members’ belief in the power of individual assassination that the same pistol was used in six high-profile shootings during an especially febrile 18-month period.

It was last, and most significantly, used on November 6, 1944 to assassinate Lord Moyne, the British Cabinet minister responsible for the Middle East during World War II. The murder, which Shamir had ordered, did change the course of history. But not for the better. Prime Minister Winston Churchill’s daring plan to resolve Arab and Jewish claims to Palestine by partitioning the country into separate states was abandoned with the killing of his life-long friend and political ally. And, three years later the first of many wars would be fought between Arab and Jew over that land’s political future.

It was the Irgun, however, that arguably had the more decisive, long-term impact on Britain. Although the rise of Israel was of course the product of many powerful forces in addition to terrorism—diplomacy, negotiation, lobbying, civil disobedience, and information operations. But in particular the Irgun’s success in attracting attention to themselves and their cause in hastening Britain’s withdrawal from Palestine in 1948 shows that—despite the repeated denials of governments—terrorism can, in the right conditions and with the appropriate strategy and tactics, succeed in advancing its practitioners’ political agendas.

This in turn taught a powerful lesson to similarly aggrieved peoples elsewhere, who now saw in terrorism an effective means of transforming hitherto local conflicts into international issues. Less than a decade later the leader of the anti-British guerrilla campaign in Cyprus adopted an identical strategy that secured that country’s independence in 1962. Similarly, Algerian nationalists fighting against France followed Begin’s strategy of provoking the security forces in hopes of alienating the population from the authorities and thereby undermining the pillars of colonial rule in the Battle of Algiers. The internationalization of Palestinian terrorism that occurred in the ’60s and ’70s would also appear to owe something to the quest for international attention and recognition that the Irgun’s own terrorist campaign pioneered a quarter of a century earlier.

Thus the foundations were laid for the transformation of terrorism in the late ’60s from a primarily localized phenomenon into the security problem of global proportions that it remains today. Indeed, when U.S. military forces invaded Afghanistan in 2001, they found a copy of Begin’s seminal work, The Revolt, along with other books about the Jewish terrorist struggle, in the well-stocked library that al Qaeda maintained at one of its training facilities in that country.

The author, most recently, of Anonymous Soldiers: The Struggle for Israel, 1917-1947, Bruce Hoffman is the director of the Center for Security Studies and director of the Security Studies Program at Georgetown University’s Edmund A. Walsh School of Foreign Service and a Senior Fellow at the U.S. Military Academy’s Combating Terrorism Center. His previous books include Inside Terrorism (2006) and The Failure of British Military Strategy within Palestine, 1939—1947 (1983).