One hundred years ago today, Nebraska became the 36th state to ratify the 18th amendment, which set Prohibition in motion a year later. Prohibition is widely, and rightly, remembered as one of the 20th century's greatest policy mistakes, and it contains more than a few lessons that remain relevant today.

The decision by the states and the federal government to outlaw the manufacture, sale, and transportation of most alcohol in the United States was born of racism, nativism, government paternalism, and moralizing religiosity.

As Harvard's Lisa McGirr writes in today's New York Times, Prohibition was fueled by white protestant disdain for urban immigrants and the saloons they frequented. Prohibition was backed by the Ku Klux Klan, and was promoted by former members of the Anti-Saloon League. The influential Women's Christian Temperance Union called for the deportation of anyone who violated alcohol law but wasn't a citizen. German beer makers were tarred as un-American. It was a moral failure, driven as much by spite towards the nation's increasing foreign-born population as by concern about excessive drinking.

But Prohibition also failed on its own terms. Instead of putting a stop to problem drinking, it criminalized it, making it more dangerous in the process. Prohibition created a violent black market for alcohol that helped empower and enrich violent criminals in the process. Problem drinkers continued to imbibe. Many drinkers switched from relatively low-proof beer to much higher proof alcohol, which was easier to transport.

Under Prohibition, drinking was still common—see, for example, this 1932 map of Harlem speakeasies, which suggests that boozy nightlife flourished—but black-market liquor was more expensive, lower quality, and sometimes dangerous to drink, since producers had to keep their work hidden from the view of authorities. That necessity bred vast corruption, as bootleggers paid off government officials, effectively making police and politicians, many of whom continued to drink themselves, partners in their illegal operations. This, in turn, bred distrust in the government, which was plainly hypocritical in its operations.

Yet the effect of Prohibition was not to turn Americans away from the government. As McGirr writes, Prohibition "cracked the door open toward other forms of regulation. Not only did Prohibition forge the edifice of the federal penal state, but growing numbers of Americans looked to the federal government for solutions to social and economic problems." Even, and perhaps especially, in failure, it created demand for further intervention.

For today's policymakers and policy influencers, Prohibition remains a cautionary tale about government overreach: It was a dysfunctional and badly run system predicated on ugly, populist notions and deluded ideas about the power of government to solve social problems. Not only did it fail to accomplish its goals, it created a host of unintended consequences that were worse than the problems it was supposed to solve.

The straightforward lessons of Prohibition are obviously applicable to any number of public policy issues making headlines today, from the opioid crisis to marijuana legalization to immigration, and our elected leaders would be wise to heed them.

But there is another lesson from Prohibition that is often overlooked—not from its beginning, but from its end, more than a decade later, with the 21st amendment, which repealed the 18th. That lesson is that, with enough time, even the worst policy mistakes can be corrected. Progress may be halting and frustrating, but America can learn from its mistakes and change its course. Yes, the effects of Prohibition lingered on for decades, in the damage it did to cocktail culture, in the institution of restrictive state liquor laws, and in the overall growth of the state. But there is little danger that full-on Prohibition will return, and slowly but surely the similarly restrictive policies that have governed marijuana are being undone.

So yes, the anniversary of Prohibition is a warning of all the ways that government policies can go wrong, and the lasting damage the worst of those policies can do. But its eventual reversal and tainted legacy also offer reasons for hope. Prohibition's end is a reminder that the very worst policies, no matter their scale, aren't locked in place, and we aren't stuck with them forever.