For the last forty years, America's approach to criminal justice has grown steadily more punitive. Successive waves of state and federal legislation lengthened prison sentences, reduced opportunities for rehabilitation, expanded the powers of law enforcement agencies, and imposed new restrictions after release. The cumulative result of these various initiatives is a sprawling prison system filled with millions of bodies, leaving deep scars on American society.

This carceral fever could be close to breaking at last. The Coalition for Public Safety, a new alliance of political groups and think tanks, is the latest signal that opposition to mass incarceration has gone mainstream. The organization unites left-leaning organizations like the ACLU and Center for American Progress with conservative and libertarian organizations like FreedomWorks, Americans for Tax Reform, and Right on Crime. Koch Industries is opening its checkbook for the venture; the ACLU received a $50 million grant from George Soros’ Open Society Foundation in December to cut national incarceration rates.

The alliance’s initial goals are modest and tangible ones. On their inaugural conference call last Thursday, group leaders frequently invoked civil-asset forfeiture and mandatory minimum sentences as their first targets for reform. “If civil-asset forfeiture is the first one we can jump on, let’s go with that and put points on the board,” said Anthony Romero, the executive director of the ACLU. Until these reforms come about, the Coalition’s greatest success could simply be inertial.

Launching a trans-partisan effort may seem odd in this polarized political climate, but it has a certain logic in the context of criminal justice. Mass incarceration, after all, was a triumph of bipartisanship. Republican contributions often receive the most attention. Ronald Reagan oversaw the dramatic expansion of the war on drugs. Willie Horton's impact in the 1988 presidential election helped deliver George H.W. Bush the presidency while suffocating criminal-justice reforms in Massachusetts and elsewhere. Conservative states like Texas, Louisiana, and Alabama saw the fastest rise in incarceration rates.

But many prominent Democrats also contributed to the carceral state’s growth. Senator Ted Kennedy championed the use of mandatory sentencing guidelines and worked with Strom Thurmond to secure the Sentencing Reform Act’s passage in 1984. Bill Clinton's 1994 omnibus crime bill, which passed Congress with the strong support of Joe Biden, Kennedy, and other major Democratic lawmakers, added $9.7 billion in new funding for prisons. As the incarceration rate jumped during the 1990s, Congress passed and Clinton signed the Prison Litigation Reform Act in 1996. The law added new barriers to prisoner lawsuits that challenged their treatment and conditions.

Liberal governors and state legislators also played their part. New York Governor Mario Cuomo, a Democratic standard-bearer in the 1980s, built dozens of new prisons during his twelve-year tenure to fill the demand created by the state’s Rockefeller drug laws. To avoid raising taxes, Cuomo turned to the state’s Urban Development Corporation to finance new prison construction. The corporation was originally designed to fund housing projects for New York’s poorest. In a dystopian way, it succeeded.

What changed the bipartisan consensus? Perhaps the most important development is the sharp decline in crime since the turbulence of the early 1990s. New research shows that incarceration bore little to no responsibility for the decline in crime, although the exact causal mechanisms are still heavily debated. Another major factor was the Great Recession, which forced states and the federal government to reckon with the high costs of large-scale imprisonment. New York City spent nearly $100,000 per inmate at Rikers Island in 2014; a year's tuition at New York University costs roughly $46,000 per student by comparison. Finally, scholars like Marc Mauer and Michelle Alexander re-framed how Americans view crime, race, and poverty in the public sphere. Like "climate change" or "immigration reform," the phrase "mass incarceration" brings semantic order to a disordered set of interconnected concepts.

These shifts blunted the "tough-on-crime" mentality that had suffused American political discourse for decades. Even the nation's highest law-enforcement official embraced the change. "Today, a vicious cycle of poverty, criminality, and incarceration traps too many Americans and weakens too many communities," said Attorney General Eric Holder in a 2013 speech to the American Bar Association. "And many aspects of our criminal justice system may actually exacerbate these problems, rather than alleviate them." Democratic stalwarts like Patrick Leahy and Cory Booker and conservative Republicans like Rand Paul and Ted Cruz now plan to propose sentencing reforms that would have been considered unthinkable a decade ago. President Obama met with some of the Smarter Sentencing Act's sponsors on Wednesday.

Cynicism comes easily at this point. A weaker bill, the Corrections Act, looks like it might have a better chance of passing Congress. Vox's Dara Lind notes that the legislation would mostly benefit whiter and more affluent inmates in a system that overwhelmingly punishes people of color and the indigent. And even beyond federal legislation, scholars like Michelle Alexander and Marie Gottschalk argue that far deeper reforms are needed to truly address the crisis. Addressing mass incarceration, they argue, requires reckoning with the racial, social, and economic scaffolding that helped build it.

Another complication is the American legal system's structure. Although we speak of “the criminal-justice system” in the singular, the United States is actually organized into fifty state criminal-justice systems with a smaller federal one superimposed over them. Unlike healthcare or immigration, no single piece of legislation can overhaul the entire criminal-justice system. Mass incarceration can only die by a thousand cuts.

At some levels, the first slices are already being made. Juvenile-justice reforms in Texas have seen significant results, with juvenile arrests dropping by one third, according to a recent report. In 2014 alone, ten states introduced laws or regulations that limited solitary confinement. California’s ambitious Proposition 47, which voters passed in last year’s election, downgraded many non-violent drug felonies to misdemeanors. Fearing a federal intervention in their prison systems, states like Alabama are taking the initiative to make reforms on their own.

At its core, mass incarceration is a story about people—over 2 million of them behind bars, with millions more on parole or probation. With a system so vast, almost any single reform may seem inconsequential. But even modest and incremental changes can change thousands of lives, when applied to such an enormous population. And the consequences of these reforms can also be measured by the individuals they affect. Eliminating or even substantially reducing mandatory-minimum sentences could save a person from years, perhaps decades, behind bars. Curtailing the use of solitary confinement as a form of punishment could preserve their mental health. Juvenile-justice reforms can reshape the course of a young person’s entire life. None of that is smallness.