In politics, it seems there is nothing new under the sun. A century ago, on 5 February 1917, Congress passed by an overwhelming majority the first legislation in American history restricting immigration. Due to chaos and conflict abroad, the bill enjoyed broad popular support, and Congress easily overrode President Woodrow Wilson’s veto. The law prohibited immigration from the Middle East and Southeast Asia, imposed literacy tests on immigrants and expanded the list of “undesirable” persons barred from entering the United States. It would remain in place until superseded by the Immigration and Nationality Act of 1952.

Two weeks ago, Donald Trump signed an executive order temporarily halting immigration and travel from seven majority-Muslim nations, suspending the U.S. refugee program and indefinitely banning refugees fleeing war-torn Syria. This odious act was met with mass protests at airports across the U.S., and the order was eventually blocked by a federal judge. Nevertheless, the Trump administration stands undaunted and has appealed the court’s ruling, setting the stage for a protracted legal battle. The motivations behind Trump’s executive order are remarkably similar to those behind the Immigration Act of 1917. Both actions were conveniently rationalized as necessary for national security. However, what truly inspired the originators of these exclusionary policies was the desire to maintain a white, Christian majority within America.

The prohibition of Asian and Middle Eastern immigrants in 1917 was the product of the waves of anti-Asian moral panic that engulfed the Western world throughout the nineteenth and early twentieth century. Similar contemptible prejudices lie beneath Trump’s executive order, clearly meant as a step towards the “Muslim ban” Trump promised throughout his presidential campaign. As the Los Angeles Times reports, the Trump administration hopes to “fundamentally transform how the U.S. decides who is allowed into the country and to block a generation of people who, in their view, won’t assimilate into American society.” The two advisers responsible for the executive order, Steve Bannon and Stephen Miller, both have ties to white nationalism and have suggested that Muslims and Hispanics are incapable of assimilating into American culture. The staying power of bigotry, racism and xenophobia in the United States raises the question of whether we, as a society and nation, have truly made moral progress.

Our last president was fond of Martin Luther King, Jr.’s famous remark that “the arc of the moral universe is long, but it bends towards justice.” References to the “arc of the moral universe” or the “arc of history” pepper Obama’s speeches. It is no doubt partially an advantageous rhetorical device that allows its user to relegate his foes and their ideas to the wrong side of history. At the same time, it is clear that Obama and other progressives really do believe that, through gradual progress, humanity will eventually achieve something resembling moral perfection. In their vision of history, the bigotry and ethno-nationalism of Trump and his ilk represent atavistic fears and hatreds that will eventually be vanquished by liberal principles. This view of historical determinism—sometimes referred to as “Whig historiography”—is the very foundation of progressivism.

But what evidence is there to support the Whig interpretation of history? A careful examination of the course of history seems to suggest that periods of advancement are instead followed by periods of reaction. The power and splendor of Rome gave way to the deprivation and bloodshed that enveloped Europe between the fifth and eighth centuries. In postbellum America, Reconstruction was followed by Redemption, the movement by Southern whites to again disenfranchise and oppress African-Americans. The lengthy period of relative peace and prosperity on the European continent during the second half of the long nineteenth century was succeeded by two cataclysmic wars. In our current neoliberal age, the advancements in economic justice forged in the New Deal and the Great Society have been crippled. After Barack Obama’s presidency, America elected Donald Trump. Even the slightest scrutiny of history and our present situation casts doubt upon the idea of progress, at least insofar as morality is concerned.

As many have pointed out, when Martin Luther King, Jr. spoke of the “arc of the moral universe,” he was speaking in an exclusively religious context (in fact, King was paraphrasing Theodore Parker, a nineteenth-century Unitarian minister and abolitionist). As a Christian, King believed that there would be an end to history, when “there will no longer be any death; there will no longer be any mourning, or crying, or pain.” Yet this would be the work of God, not the culmination of liberal progress. King would no doubt have disagreed vehemently with the suggestion that the Earthly City could ever be perfected. Indeed, towards the end of his life, he frequently voiced pessimism about the prospect of economic and racial justice in this world.

If our politics will always be a struggle between the forces of equality and the forces of intolerance, should we not abandon all hope? I must admit that this course of action at times recommends itself. Nevertheless, there are reasons to resist despair and continue striving for a more just society. Contemporary American left-liberalism, at its best, fights for an equitable distribution of wealth, universal health care, protection from discrimination, robust voting rights and freedom of expression. These rights and public goods are not simply means to an end; rather, they are ends in and of themselves. As such, they are worth pursuing, even if they are not fully and permanently realized.

In the end, the world we inhabit right now is “the true and only heaven,” to use a phrase the historian and moralist Christopher Lasch borrowed in turn from Nathaniel Hawthorne. We should use the short span of time allotted us to bend the arc of the moral universe as close to justice as possible. As years go by, that arc will likely be bent back towards oppression and cruelty. Dark ages will, in turn, be transformed through the toil of the righteous. The bigotry, racism and xenophobia responsible for Donald Trump’s cruelty will always be with us. So too will the spirit that has compelled thousands of Americans to join protests, voice their outrage to members of Congress and donate to civil liberty advocacy groups. This is the story of political society from the very beginning, and its consistency should give us some sense of direction in the days ahead.