Democratic presidential candidate Hillary Clinton speaks at Texas Southern University last week. (Thomas Shea/Getty Images)

This weekend, Hillary Clinton will unveil her “vision for the country” at a mass rally at the FDR Four Freedoms Park in New York City. Her campaign indicates that she’ll reveal a fuller picture of her economic policies in what is being billed as her official campaign launch.

But the stunning Louis Kahn memorial to Roosevelt can be more than just a setting for Clinton. It can inspire her to a far broader and bolder mission: to challenge directly, as Roosevelt did, the constrained notion of freedom that has dominated our politics since Ronald Reagan, and to offer a more expansive, empowering view of America’s experiment.

As historian Eric Foner has shown, freedom has always been a contested concept in the United States. In different eras, it has taken on different meanings. For the founders, it meant freedom from political autocracy, and from royalists with special privileges from the crown. Speaking in 1936, Roosevelt argued in the midst of the Great Depression, that industrialization had produced a “new despotism” of “economic dynasties.” Within our borders, Roosevelt argued, “popular opinion is at war with a power-seeking minority . . . an economic autocracy.”

At the start of World War II, Roosevelt rallied Americans to the noble cause of the “four freedoms” — freedom of speech, freedom of religion, freedom from want and freedom from fear (which he translated as, among other things, global disarmament). These were the basis of the Economic Bill of Rights that Roosevelt detailed in his 1944 State of the Union address, arguing that “true individual freedom cannot exist without economic security and independence.”

Over the last several decades, the conservative era launched by Reagan has promoted a far more limited definition of freedom. For conservatives, freedom is centered in markets, free from government interference. The entrepreneur, not the citizen, is the central actor. Government is the threat; the best thing it can do is to get out of the way. With the glaring exceptions of global intervention and the bloated military, conservatives argue that freedom entails privatization, deregulation, limiting government’s reach and capacity.

For years, Democrats chose to tack to these conservative winds. Bill Clinton’s New Democrats echoed the themes rather than challenge them. “The era of big government is over,” he told Americans, while celebrating “ending welfare as we know it,” deregulation of Wall Street and mass incarceration.

Barack Obama came to office in the worst recession since the Great Depression, after Wall Street’s excesses blew up the economy. Government had to act to save the economy. But Obama chose consciously not to challenge the conservative limits on what freedom means. The banks got saved but homeowners didn’t. The rich recovered but working families didn’t. The conservative notion of freedom once more resulted in an economy serving the few, and a politics corrupted by money.

This is Hillary Clinton’s historic opportunity. The greatest threat to freedom now is posed by the entrenched few that use their resources and influence to rig the rules to protect their privileges. She would do a great service for the country — and for her own political prospects — by offering a far more expansive American view of what freedom requires, and what threatens it.

Clinton should make it clear to Americans that in a modern, globalized world, we are in the midst of a fierce struggle between economic royalists and a democratic citizenry. If we are to protect our freedoms, citizens must mobilize to take back government from the few, to clean out the corruption and to curb the oppressive power of the modern day economic royalists.

In this struggle, we must return to expanding and defending the four freedoms: protecting freedom of speech and our liberties in the face of a national security state and a seemingly unending war on terror; protecting freedom of religion by strengthening the separation of church and state; expanding freedom from want by lifting the floor under workers, insuring every child a healthy start, providing free public education from pre-k to college, rebuilding the United States and putting people to work; strengthening freedom from fear by returning to defending our citizens, not policing the world.

Freedom in today’s America requires making our diversity a strength, not fanning fears of immigrants and foreigners. It means defending the equality of women and the personal freedoms and rights that have been won through great struggle, not succumbing to a backlash against them. And it means freeing our elections and our leaders from the corruptions of big money politics.

Clinton has said she wants to be the champion of “everyday Americans.” She has criticized a system that is rigged to benefit those at the top. She has delivered bold speeches with vital reforms on immigration, mass incarceration and voting rights. She told fast food workers striking for $15 dollars an hour and a union that she wants to be their champion.

The big unanswered question is whether she is prepared — as FDR was — to take on the economic royalists of this day. Where will she stand on the corporate trade deals like the Trans-Pacific Partnership and its private corporate court system? Will she favor fair taxes on the rich and corporations to rebuild the United Statesand put people to work? Will she make the case for vital public investments — in new energy, in infrastructure, in education and training — that have been starved for too long? Will she call for breaking up banks that are too big to fail? Will she favor expanding social security, now that corporations have virtually abandoned private pensions?

No single speech can or should answer all these questions. Far more important is to offer Americans a bolder conception of freedom in the American experiment, and to make it clear who stands in the way. That would offer us the vision Americans desperately need to hear — and set up the debate that America must decide.

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