We are marking the 150th anniversary of the American Civil War. So what? Most Americans seem indifferent.

That's a pity. The Civil War can tell us a great deal about ourselves, then and now.

We have an unfortunate history of plunging into wars for God and democracy that have often made a mockery of both. If we can use this anniversary to learn more about why we rush to war, it will be an exercise worth undertaking.

More than 750,000 men died in the Civil War. Extrapolated to today's population, the death toll would be close to 10 million. Consider also the millions who mourned the loss of their husbands, brothers, and sons, and those soldiers who survived yet returned home maimed in mind or body.

Most historians today would lament the casualties but commend the outcome: the liberation of four million slaves. I disagree. The Civil War was not a just war; it was a war of choice brought on by an insidious mixture of politics and religion that caused our political process, and ultimately the nation, to disintegrate.

The war did indeed end slavery, but could we have achieved this noble objective without the slaughter? The United States was the only slaveholding nation that abolished the institution with a civil war.

Republicans' rise

Our government governs best from the center and depends on compromise. By 1861, however, the Bible had replaced the Constitution as the arbiter of public policy, particularly on the issue of extending slavery into the Western territories. Framing slavery as a moral cause rendered compromise unlikely, for you cannot compromise with sin. The party in power, the Republicans, deployed evangelical dogma to raise the stakes of political discourse.

The party's ideology was rooted in the Second Great Awakening, a national religious revival begun in the early 19th century. Within a generation, nearly 40 percent of religious Americans were members of evangelical Protestant denominations. The message of evangelicals was simple: If you accept Jesus Christ as your personal savior, you will be saved and enjoy eternal life in heaven.

In the North, however, evangelicals used the Gospel not only to convert individuals, but to reform society. They viewed America as God-blessed, ordained to conquer a continent and spread democracy and Protestant Christianity across the land and, eventually, the world.

To accomplish this great objective, they believed, America must expiate its sins, foremost among them slavery and the Catholic Church. Historians have soft-pedaled the religious bigotry of Northern evangelicals and their allies, praising their antislavery stance instead. However, you cannot discuss one without accounting for the other, because they merged in the political arena.

Also, we should not confuse antislavery with pro-black: Many antislavery Northerners believed, along with the vast majority of whites (including Abraham Lincoln), that African Americans were inferior.

An eroded center

Beginning in the early 1840s, small evangelical political parties emerged in the North demanding government action against slavery and the Catholic Church. Violent clashes of Protestant and Catholic gangs took place in the streets of major Northern and border cities.

Between 1847 and 1857, more than a million Irish Catholics emigrated to the United States to escape the potato famine. The sudden influx of Catholic immigrants alarmed evangelicals, especially those in the North.

At the same time, the controversy over the extension of slavery in the territories worsened.

Northerners concerned about the Catholic "invasion" and slavery formed a new political party in the mid-1850s, the Republicans. In 1858, when Lincoln ran for the U.S. Senate in Illinois as the Republican candidate, the party cited "The Two Despotisms — Catholicism and Slavery — Their Union and Identity."

Lincoln was neither a religious bigot nor an evangelical Christian. But his speeches and writings in the late 1850s became increasingly messianic, as if some great conflagration were about to consume the country for its sins. His famous "House Divided" speech, in 1858, derived from Matthew 12:25: "And Jesus knew their thoughts, and said unto them, 'Every kingdom divided against itself is brought to desolation; and every city or house divided against itself shall not stand.' "

Self-righteousness eroded the vital center of American politics. Northerners and Southerners flung biblical verses at each other, deepening the divide. When the Republicans, avowedly evangelical and proudly sectional, took control of government in March 1861, Southerners rightly expected the worst. And the worst happened.

Young men marched off to war as crusaders. But the horrors of the war soon overcame the recruits' religious zeal. At the Battle of Shiloh, in Tennessee in April 1862, a Confederate soldier cursed the war he had once welcomed: "Oh! What suffering, what misery, what untold agony this horrid hell-begotten war has caused." Soldiers at Shiloh witnessed the destructive potential of modern weaponry and outdated tactics: fields puddled with blood and strewed with dead men, animals tearing at their entrails.

Union Gen. William Tecumseh Sherman advised his men not to look for God on the battlefield: "When preachers clamor ... don't join in, but know that war ... follows its own laws, and turns not aside even if the beautiful, the virtuous, and charitable stand in its path." This is the war that often gets lost in the self-congratulatory narratives of the history books.

And what of the former slaves, on whose behalf this carnage was allegedly undertaken? The Civil War sealed their freedom, but little else. It would be more than a century before African Americans attained basic rights.

In 1888, which marked the 25th anniversary of the Emancipation Proclamation, Frederick Douglass, the great black abolitionist, pronounced the document a "fraud." The vast majority of blacks still toiled on the South's farms and plantations, often in conditions that some historians have called worse than slavery.

‘Slavery's parent'

Might not peace, rather than war, have put an end to slavery and secured the rights of African Americans much sooner? Capt. Oliver Wendell Holmes Jr. thought so. Writing to his father after the devastating Union defeat at Fredericksburg, Va., in December 1862, which he called "a hideous human waste," the disillusioned soldier reasoned that "if it is true that we represent civilization, which is in its nature, as well as slavery, diffusive & aggressive, and if civilization & progress are the better things, why, they will conquer in the long run ... and will stand a better chance in their proper province — peace than in war, the brother of slavery ... [War] is slavery's parent, child and sustainer at once."

In commemorating the Civil War, we should remember that wars are easily made, difficult to end, and burdened with unintended consequences and unforeseen human casualties.

We should also keep in mind that there is no higher law than the Constitution. That is America's Scripture.

David Goldfield is a professor of history at the University of North Carolina, Charlotte, and the author of "America Aflame: How the Civil War Created a Nation." He wrote this for the Free Lance-Star of Fredericksburg, Va.