Born in the Lithuanian shtetl of Kurshan in 1932, Donald Kagan came to the U.S. with his mother when he was only two years old, following the death of his father. He grew up in the Brownsville neighborhood of Brooklyn and attended Brooklyn College, where he developed an interest in ancient history. As an adult he became one of the foremost experts on ancient Greece and the Peloponnesian War, spending most of his career teaching at Yale University, where he also served as dean. He died last Friday at the age of eighty-nine.

In a seminal 1987 essay for Commentary, Kagan outlined the historical lessons of World Wars I and II, and applied them to what he called World War III—that is, the cold war. While since 1918 historians had argued that French and British unwillingness to accommodate Germany had helped to bring on the First World War, Kagan disagreed:

The question is, what “accommodation” could the European states have made to the German “upstart” that would have brought satisfaction to Germany and stability to Europe? What, in fact, did Germany want? At the turn of the century Germany was the strongest military power in the world. It also had the strongest and most dynamic economy on the continent. In 1897, without any previous naval tradition, without any new challenge from the sea to justify an expensive change in policy, the Germans undertook the construction of a major battle fleet concentrated in the North Sea where it could threaten traditional English naval superiority and the security that went with it. The British gradually became alarmed as they came to recognize the threat Germany might pose.

The chief lesson that emerges from seeing the outbreak of World War I from this perspective is not the one learned by [most historians]. It was not the unwillingness of the British to make reasonable concessions to a new competitor for power and prestige that allowed the war to come, but their refusal to pay the high price of deterring an ambitious opponent committed to changing the balance of power to their disadvantage and danger.

Britain, having learned the wrong lessons from the Great War, went on to apply these lessons to a resurgent Germany at Munich, leading to disastrous consequences. Such confusion still dominated sophisticated thinking in the 1980s, when elite opinion generally agreed that Ronald Reagan—by pursuing the arms’ race, confronting the Soviet Union in Afghanistan and Latin America, and calling on Germans to tear down the Berlin Wall—was increasing rather than decreasing the risk of war.

History proved Kagan right, although he hardly could have predicted that Berliners would tear down the wall two year later, or that in another two years the USSR would collapse. But the lessons Kagan drew concerning the importance of military preparedness, the need to stand up to rather than to appease enemies, and the willingness to use force when necessary remain hard to learn, although they apply to present conflicts with China, Russia, and even Iran. His essay concludes:

All of that runs against the grain and is terribly difficult in free societies that enjoy the luxuries of economies designed for the pleasure and happiness of their people and systems of political competition in which the material advancement of the citizens has very high priority and in which the illusion persists that isolation is still possible. But the 20th has been a hard century, and the 21st will be no less hard. The study of our two analogies [to the two world wars] suggests that nothing short of an honest look at reality . . . will be needed for survival.

For some time, opponents of U.S support for Israel have been urging the White House to end the war in Gaza, or simply calling for a ceasefire. Douglas Feith and Lewis Libby consider what such a result would actually entail:

Ending the war immediately would allow Hamas to survive and retain military and governing power. Leaving it in the area containing the Sinai-Gaza smuggling routes would ensure that Hamas can rearm. This is why Hamas leaders now plead for a ceasefire. A ceasefire will provide some relief for Gazans today, but a prolonged ceasefire will preserve Hamas’s bloody oppression of Gaza and make future wars with Israel inevitable.

For most Gazans, even when there is no hot war, Hamas’s dictatorship is a nightmarish tyranny. Hamas rule features the torture and murder of regime opponents, official corruption, extremist indoctrination of children, and misery for the population in general. Hamas diverts foreign aid and other resources from proper uses; instead of improving life for the mass of the people, it uses the funds to fight against Palestinians and Israelis.

Moreover, a Hamas-affiliated website warned Gazans last month against cooperating with Israel in securing and delivering the truckloads of aid flowing into the Strip. It promised to deal with those who do with “an iron fist.” In other words, if Hamas remains in power, it will begin torturing, imprisoning, or murdering those it deems collaborators the moment the war ends. Thereafter, Hamas will begin planning its next attack on Israel:

Hamas’s goals are to overshadow the Palestinian Authority, win control of the West Bank, and establish Hamas leadership over the Palestinian revolution. Hamas’s ultimate aim is to spark a regional war to obliterate Israel and, as Hamas leaders steadfastly maintain, fulfill a Quranic vision of killing all Jews.

Hamas planned for corpses of Palestinian babies and mothers to serve as the mainspring of its October 7 war plan. Hamas calculated it could survive a war against a superior Israeli force and energize enemies of Israel around the world. The key to both aims was arranging for grievous Palestinian civilian losses. . . . That element of Hamas’s war plan is working impressively.