With the passing of Elouise Cobell, a proud member of the Blackfeet Nation of Montana, we have lost a champion of Native American rights. Her persistent and determined leadership in the pursuit of justice for Native Americans will leave an enduring legacy.

As treasurer of the Blackfeet Nation, Elouise spoke out when she saw that the federal government had failed to account for billions of dollars that it owed to hundreds of thousands of her fellow Native Americans. In 1996, she filed suit, and for 15 years, tirelessly led a legal battle, with seven trials, 10 appeals, and dozens of published decisions. She fought her battle not just in the courts, but in the halls of Congress before finally securing justice for more than 300,000 American Indians and Alaska Natives in the form of a $3.4 billion settlement.

The agreement reached in Cobell v. Salazar marked the largest government class-action settlement in our nation’s history. The scholarship fund this settlement established will give more Native Americans access to higher education. Tribes will have more control over their own lands. Elouise’s tireless efforts strengthened the government-to-government relationship with Indian country, and a generation of Native Americans and all Americans has seen the promise of justice realized.

Last December, I had the privilege to meet with Elouise in the Oval Office prior to signing into law a bill to make things right. The Claims Resolution Act of 2010 is a direct result of the settlement that bears her name. It is proof of an enduring American idea – that change is always possible.

But change is never easy. It doesn’t come overnight. In this case, it took 15 years. For 15 long years, despite obstacles and setbacks, Elouise Cobell pressed on with a defiant yet humble refusal to accept the world as it is, and a quiet determination to reach for the world as it ought to be.

“I never started this case with any intentions of being a hero,” she said. “I just wanted this case to give justice to people that didn’t have it.”

In the face of daunting odds, Elouise remained driven by the belief that America is a place where tomorrow can be better than today – and convinced that this is a country where hard work and great resolve can make a difference.

That is what makes this country special. Even when we haven’t always lived up to our highest ideals, we know we can right a wrong; even if we enjoy certain rights, we know are not truly equal until everybody enjoys those rights; even if we are doing well, we know we have a responsibility to leave a better future for our children, and the obligation to try.

That is what Elouise Cobell did. We mourn her passing, thank her for the legacy she left behind, and commit ourselves to that same passionate pursuit of a more perfect union.