espite its imperfections, democratic government remains the best way to institutionalize the rights and freedoms we cherish. It depends on certain crucial principles: free and fair elections, free speech, freedom of religious expression, and domestic peace and security.

War is a less obvious principle, yet there is a strong correlation between war and democracy. In Forged Through Fire: War, Peace, and the Democratic Bargain, John Ferejohn and Frances McCall Rosenbluth argue that:

[t]he short answer to the question of how war can promote the cause of democracy is simple: during wartime, when governments are desperate for manpower to help them fight more effectively, they may be forced to pay more attention to the common man.

Ferejohn and Rosenbluth aren’t the first to suggest war and democracy are connected. Jared Diamond’s Guns, Germs, and Steel: The Fate of Human Societies (1997), and Niall Ferguson’s The Pity of War (1999), make similar arguments. What makes Forged Through Fire unique is that it tackles a wide range of world events, from ancient Greece to the modern U.S. Placing the concept of war directly within each battle, political and physical, it shows that war is to democracy what democracy is to war: an important partner in the eternal struggle for survival and success.

In classical Athenian democracy, the “strains of warfare shaped Athenian institutions in discernible ways that establish[ed] a benchmark against which to measure subsequent constitutional forms.” For this to occur, parallel changes involving class, social status, and nationalist identity were necessary. Cleisthenes, “the scion of an exiled aristocratic family,” led the charge when he helped “transformed elite rivalry into patriotic self-defense.”

Forged Through Fire argues that war shaped Athenian democracy in two ways: “the compatibility of democracy with an effective foreign policy, and good governance.” Successful wartime policy-making helped increase the influence and reputation of democratic decision-making, while decreasing the possibility of the democratic experiment being reduced to rubble via tyranny and authoritarian rule.

A similar story was borne out during the growth of Europe’s monarchies. As centralized monarchy replaced decentralized feudalism in France and Spain in the late Middle Ages, “wars of conquest, not voluntary association, created the modern nation-state.” The steady increase in commercial wealth led to a merchant class that forged a revenue-based economy. In turn, military technology began to transform through the advent of gunpowder and more advanced weaponry. The advantage in combat “went to those lords who could afford to buy more and better guns and recruit bigger armies to use them.”

Since “monarchies could buy armies with money,” war played an important role in the rise of bourgeois Europe. The divide between rich and poor, landowner and serf, didn’t disappear. Yet, the rise of European monarchies led to “the conditions under which war forced kings to share decision-making power with the owners of wealth and, in more extreme cases, with the men supplying their labor.” The roots of European democracy and capitalism sprouted during a period dominated by power struggles among the nobility.

In the mountain republics of Switzerland and Austria, the authors point out, “History has shown that people living in hard-to-reach places tend to govern themselves more or less democratically.” Meanwhile, “when it comes to defending themselves from the outside, the more everyone is needed to fight, the more these societies are likely to aim for near unanimity.” This means, “War, or the threat of war, can push in a democratizing direction when each person’s contribution is vital, and defensible terrain can have that effect by leveraging each person’s contribution to communal safety.”

By the 19th century, “wars of national mobilization” such as the French Revolution “forced workers and employers to eventually reach a compromise for the sake of common defense.” To put it another way, “Chest-thumping nationalist rhetoric was nearly loud enough to drown out the howls of leftist radicals and in fact won over many ordinary citizens.”

While the growth of classical liberalism and Burkean conservatism in Europe didn’t prevent the failed 1848 revolutions in France, Italy, Austria and Germany—or the 1917 Russian Revolution, for that matter—it did boost democracy, liberty, and freedom.

The World Wars formally ensconced the war-democracy axiom into modern society. This evolution was aided by representative democracies like Britain, which “managed to mobilize both manpower and capital for a successful war effort.” While Nazi Germany and Communist Russia and China could “raise vast armies in the modern world by instilling fear, promising economic benefits, and appealing to national pride,” these tyrannies “paid unintended tribute to the democratic model by publicly insisting that their governments embodied a more perfect blend of liberties.”

The 20th century also “pulled money and manpower together in collective self-defense,” according to Ferejohn and Rosenbluth. Taxation was used to fund wars and military efforts in western democracies for safety and security, whereas various institutions such as universal suffrage and reform-minded Parliaments involved larger segments of society. This mutually exclusive trade-off between war and democracy is a recurring theme in Forged Through War.

Finally, war played an intriguing role in U.S. race relations. There’s little doubt that “America’s wartime mobilization was slow to include nonwhites: in every war until Vietnam, black soldiers were underrepresented in the military relative to their numbers in the population.” Presidential administrations either hesitated or flatly refused to recruit them, and some black community leaders “wondered aloud why blacks should fight for a country that oppressed them.”

This perception began to change over time. Black regiments fought side-by-side with white soldiers, and made important contributions during the Civil War and the two world wars. While “political equality for blacks moved forward at least within the military,” racist behavior remained in some military circles. Vietnam, “the first war with fully integrated combat units and black recruitment,” brought this tumultuous period to an end—and helped advance the civil rights movement and wider acceptance of the black community in the U.S.

Forged Through Fire, in short, superbly explicates how war has shaped the development of liberal democracy’s principles and practices.