Last Tuesday, two widows of the Israeli Olympians murdered at Munich in 1972 revealed that the eight Palestinian terrorists beat the hostages who survived their initial assault. The attackers also shot Yossef Romano when he resisted, then castrated him. These horrifying details, sandwiched between the Paris massacre and the San Bernadino bloodbath, amid the latest wave of Palestinian violence, reinforced a fact that terrorist- deniers and Palestinian apologists deny: The world’s tolerance for Palestinian terrorism, starting in the 1970s, made it the gateway crime to Islamist terrorism – understanding a gateway crime as both evil and trailblazing, normalizing. As one friend cleverly noted: “ The suicide vest found in the garbage bin in Paris might as well have had ‘Made in Palestine’ stitched on it. Guess that’s a label the European Union lets into the continent.”Most academics today are too politically correct to admit it – and too busy boycotting democratic Israel. But when future historians connect the dots to explain the origins of al-Qaida, Islamic State and today’s scourge of Islamist terrorism, the pattern will be undeniable. Yasser Arafat was the grandfather of Osama bin Laden and all modern terrorists. Moreover, Western appeasement of Palestinian terrorism – cravenly displayed at Munich – proved that claiming “terrorism doesn’t pay” is delusional: terrorism works thanks to Western weakness. Violence put the Palestinians on the international agenda and cast them as the ultimate oppressed Third Worlders to many totalitarian leftists – who today exaggerate Palestinians’ suffering, importance and impotence.In September 1972, the International Olympic Committee president, Avery Brundage, became the sniveling symbol of Western appeasement. More protective of his games than the kidnapped athletes, he allowed the Olympics to continue for 10 hours as the Palestinians tortured the Israelis. Then, after the terrorists murdered the hostages and one German policeman during Germany’s botched rescue attempt, Brundage insisted the games continue after a short 24-hour pause. One Los Angeles Times columnist wrote: “It’s almost like having a dance at Dachau.”The Olympic Committee has never commemorated the murdered Israelis with a moment of silence (although one is planned for 2016), hoping not to “politicize” the games, meaning anger Arabs and Muslims.Barely two months after this debacle, West Germany used a false hijacking ruse to free the three surviving terrorists. In return, the PLO promised not to attack Germany. In 1999, one terrorist, Jamal al-Gashey, boasted: “I am proud of what I did at Munich because it helped the Palestinian cause enormously. Before Munich the world had no idea about our struggle, but on that day the name of Palestine was repeated all over the world.” In September 1970, Palestinian terrorists hijacked planes and destroyed them in Jordan, but Munich became their big international premier.Six months after Munich, on March 1, 1973, America – under a supposedly tough Republican Richard Nixon – caved despite losing two diplomats in a Palestinian raid against the Saudi embassy in Khartoum. The two Americans, Cleo Noel and George Curtis Moore, along with a Belgian diplomat Guy Eid, were the only hostages murdered – after Yasser Arafat sent the terrorists a coded radio message, asking: “Why are you waiting? The people’s blood in the Cold River cries for vengeance.” “Cold River” was the pre-arranged code for “kill them.”The Sudanese soon freed all eight terrorists and the Americans never hunted down these killers. Less than two years later, in November, 1974, Arafat addressed the UN General Assembly. Two decades after that, this unrepentant murderer of Americans would win the Nobel Peace, be the most frequent foreign guest Bill Clinton hosted at the White House and bring his people to the brink of a peace treaty and their own state, only to lead them back to terrorism, delegitimization and cries to exterminate the Jewish state.The Palestinians chose well in targeting Israel, especially during the 1970s. Directing terrorism against the Jewish state triggered decades of blaming the victims and excusing the perpetrators. The anti-Semitic hostility so many Westerners have toward Israel, the Jew among the nations, reinforced the growing post-Sixties culture of Western guilt, self-abnegation, appeasement and enabling of violent enemies – as long as they could define themselves as people of color. Radicals cast democratic Israel, forced to defend itself, as an imperial force not an embattled state, while casting Palestinian terrorists as freedom fighters not pathological killers.Rather than noting how few peoples suffering far more turn terrorist, rather than wondering why Palestinians targeted innocent women, children, elders, Blame Israel Firsters assumed that Palestinians’ cruelty somehow reflected Israeli cruelty. Israel must be very guilty of intense oppression to merit such hatred, the politically correct assumed, rather than scrutinizing the Palestinian death cult that fed off anti-Semitism and Islamic fundamentalism.Arafat’s success and the West’s limp response helped weaponize an exclusivist, bigoted, triumphalist Islamist ideology, inspiring al-Qaida, Islamic State and others.Even today, President Barack Obama hesitates to label terrorism terrorism and dodges the phrase “radical Islamism” – even when a jihadist major shot up Fort Hood in 2009 or a San Bernardino shooter posted an IS manifesto. True, Obama has hunted some terrorists aggressively, but his ideological confusion has emboldened terrorists – and reflects this broader international muddle in facing evil.If I were Palestinian or Muslim, I would be ashamed. So far, the great Palestinian contribution to civilization has been terrorism; “Palestinian” as a modifier most frequently appears before the word “terrorism” – 32 million times, a Google search shows. The phrase “Islamic terrorism” appears 201 million times. Don’t they want to be known for constructive contributions? Without a robust internal critique, among Palestinians, among Muslims, terrorism will continue. Golda Meir’s aphorism needs updating. Yes, Palestinians must love their children more than they hate our own before peace comes. And Palestinians must also become terrified of being considered terrorists.The writer is the author of The Age of Clinton: America in the 1990s, just published by Thomas Dunne Books of St. Martin’s Press. He is professor of history at McGill University and a Visiting Scholar this fall at the Brookings Institution. Follow on Twitter @GilTroy www.giltroy.com.