slog, but not without rewards: that’s what best describes this account of Americans who opposed U.S. participation in the European War of 1914–1918. While Michael Kazin, a historian of progressive bent who teaches at Georgetown University, tells an important story, his book suffers from a want of zip. The narrative meanders. The prose lacks sparkle. Still, for the patient reader, War Against War offers much to reflect upon.

Kazin’s subject is what he calls “the largest, most diverse, and most sophisticated peace coalition” to that point in all U.S. history. Not until the Vietnam War a half-century later would there be an antiwar movement “as large, as influential, and as tactically adroit.”

Perhaps so, but the American peace coalition that flourished a century ago failed abysmally. It succeeded neither in keeping the country out of the war nor in insulating the home front from war’s corrosive effects once the U.S. eventually intervened.

In what was not even remotely a contest of equals, the forces favoring war proved overwhelming. An approach to “neutrality” that mortgaged American prosperity to Anglo-French victory fostered decidedly unneutral attitudes on Wall Street and in Washington. Ultimately, however, arguments for staying out of war fell prey to vast ideological pretensions. As the stalemate on the Western Front dragged on, more and more Americans succumbed to the conviction that Providence was summoning the United States to save Civilization itself. Foremost among those Americans was President Woodrow Wilson.

“I wish the United States had stayed out of the Great War,” Kazin writes. I share the sentiment. From the outset, that conflict was a mindless exercise in mutual self-immolation. The belated U.S. entry into the war did nothing to redeem it. Even if justified by the supposed imperative of destroying German militarism, the eventual Allied victory to which the United States contributed at the cost of 116,000 American dead had the opposite effect. In short order, German militarism came storming back stronger than ever. Meanwhile, other deadly viruses unleashed by the bloodletting of 1914–1918 were wreaking havoc. Even today, the consequences haunt us.

The coalition forged to prevent the United States from being drawn into the European slaughterhouse was nothing if not heterodox. Kazin describes an informal partnership consisting of four distinct elements: progressive Republicans, mostly from the upper Midwest, with Wisconsin Sen. Robert La Follette their standard-bearer; Southern populists, the racist North Carolina Democrat and House Majority Leader Claude Kitchin prominent among them; members of the Socialist Party, largely (but not exclusively) concentrated in New York City, with dapper labor lawyer and perennial office-seeker Morris Hillquit their spokesman; and a mix of political activists ranging from social reformers such as Jane Addams and Emily Balch to uncompromising radicals such as Crystal Eastman and her brother Max.

Breadth did not translate into unity or cohesion. The entities forming the peace movement entertained varied priorities, the avoidance of war not necessarily numbering first among them. Depending on the particular group, preserving white supremacy, resisting Wall Street, pressing for women’s suffrage, helping the downtrodden, promoting temperance, organizing workers, or calling for the overthrow of capitalism ranked right alongside a determination to keep the United States from intervening in Europe.

Unity was imperfect and therefore contingent. The glue holding things together was weak. As the closest thing to an umbrella organization, the American Union Against Militarism (AUAM) was the loosest form of confederation, rather than an actual union.

So while the anti-warriors who rallied against U.S. entry into the Great War achieved a degree of prominence, they wielded little clout. They made noise without actually making a difference, in large part because they proved unable to win over President Wilson.

From 1914 through 1916, Wilson gave peace proponents a respectful hearing and conveyed a sense of sympathy with their cause. They reciprocated and considered the president an ally. Indeed, when Wilson in 1916 won reelection to a second term, having campaigned on the slogan “He kept us out of war,” the AUAM persuaded itself that the president’s hairbreadth victory was “due primarily to the fighting pacifist sentiment in the United States.”

Whether or not Wilson himself shared that assessment, he soon thereafter threw in with those who had come to see Germany as the embodiment of evil. Destroying evil at its source, he now insisted, had become imperative. Although the peace lobby gamely refused to give up the fight, last-ditch efforts to forestall U.S. entry into the war by demanding a nationwide referendum on the issue—let the people decide—went nowhere. In April 1917, by a tally of 82 to 6 in the Senate and 373 to 50 in the House, Congress handed Wilson his war mandate.

To their credit, peace-movement leaders still refused to throw in the towel. They opposed Wilson’s demand to enact conscription, albeit to no avail. With equally little success, they mounted protests against administration efforts, endorsed by Congress and enforced by pro-war vigilantes, to criminalize criticism of U.S. war policies. Although U.S. participation in the conflict lasted a mere 19 months, never in American history have basic rights to speak and assemble been more widely and more egregiously violated. Using the crusade “to end all wars” as a pretext, federal authorities ran roughshod over the Constitution until war-induced hysteria finally ran its course following the infamous race riots and Red Scare of 1919–1920.

Once the fever broke, Americans wasted little time in deciding that entry into the World War had been a huge mistake, a view that persisted throughout the 1920s and well into the 1930s. Kazin sees the shift in opinion as vindicating the peace movement ex post facto. Mark me down as unconvinced. Factors other than the arguments advanced by peace activists—for starters, the thoroughly perverse results of the Paris Peace Conference—reshaped American opinion.

Peace advocates had waged a gallant fight. In the face of great adversity—ridicule, harassment, even the prospect of imprisonment—they exhibited admirable courage and tenacity. And they correctly anticipated many of the ill effects that would befall the United States should it abandon its tradition of steering clear of European squabbles. One might quibble with Kazin’s assertion that this was “the last mighty attempt” to prevent the establishment of a national-security apparatus “equipped to fight numerous wars abroad while keeping a close watch on the potentially subversive activities of its citizens at home.” But the militarization of the American consciousness that occurred during World War I certainly served as a precursor for what was to come during World War II and the Cold War, not to mention in the aftermath of 9/11.

The resistance that formed during the period of 1914–1918, Kazin believes, was “by definition, profoundly conservative.” In that opponents of the war sought to preserve something they considered precious—keeping at bay the contagion of great power politics—that judgment is surely correct. Yet the fact is that resistance accomplished next to nothing. Instead, the war and U.S. participation in it opened the floodgates to changes to which, even today, conservatives have not devised an adequate response.

Are there insights that we can draw from that failure? That prospect is what first drew me to War Against War, which I read in the days immediately preceding Donald Trump’s inauguration. As do others, I feel considerable trepidation when contemplating the course that our 45th president is likely to follow. As a corrective to my dour mood, I picked up this book hoping to find inspiration. Instead, it reinforced my sense of pessimism.

Today, long gone is any aversion to war that Americans might once have felt. Principled opposition to war has been consigned to the margins of national politics. In the Senate, there is no heir to Robert La Follette. And contemporary equivalents of Jane Addams don’t get invited to the White House to consult on foreign policy.

Against steep odds, Kazin’s protagonists came up short. Today those odds have become steeper still.

Andrew Bacevich is writer-at-large with The American Conservative.