Exactly a century ago, a mob of white people killed hundreds of African Americans in Tulsa, Oklahoma, in perhaps the worst race massacre in the United States, and destroyed the entire town. In the 100 years since then, the US government, media and social groups have not only maintained a studied silence on what has come to be known as the Tulsa Race Massacre, but also prevented people from revealing the truth, ostensibly to obliterate this black day from US history.

Yet the US sees itself as the greatest defender of human rights and boasts of its political system of "checks and balances". Let alone correcting the wrongs, the US administrations over the years have not even apologized for the heinous crime.

Even today, many questions about the Tulsa massacre have not been answered. There is a need therefore to make the details of the massacre public so the world can see for itself the hypocrisy behind the US' human rights claims.

How could the white supremacists slaughter so many people? The Tulsa neighborhood was known as the "Black Wall Street", which means the African-American residents there were relatively well off. But that doesn't mean they had enough weapons or were prepared to fight the armed mobs of thousands of white people. Apart from this, two other key factors made the massacre possible.

The first was the local government's support to the whites－the police officers turned a blind eye to the violence unleashed by the white supremacists and instead arrested those African Americans who resisted the white attackers.

The other factor was the inaction of the then president Warren G. Harding. As a result, the federal government sat idle during the violence.

Why have successive US administrations since then not openly spoken about the massacre and why has the Congress, which claims to be very sensitive to human rights issues, never commented on it?

First, American people's values are inseparable from their religious beliefs, and since Americans have been made to believe they are God's chosen people and represent the most advanced society in the world, they believe they cannot make any mistakes.

Second, the belief of belonging to a master race is ingrained in many white Americans. So, many of them might still justify any action taken to destroy black communities, especially those that dared to become richer than some white people.

Third, since white people comprise the majority of voters in the US and condemning white supremacists could mean losing their votes, neither Democrats not Republicans dare to take the political risk of doing so.

Also, soon after the massacre, the local government said what had happened in Tulsa was a riot, meaning it was not a mass killing of African Americans by white supremacists, and the media swallowed this false narrative hook, line and sinker.

At the legal level, racial discrimination may not be overt, but covert racial discrimination is rampant in the US, the election of an African American president notwithstanding.

In reality, the social status of and income gap between black and white people have not changed much over the years. And if some black people dare to acquire higher qualifications or have better business acumen and make more money than some white people, they risk being targeted by white supremacists.

That the government and social organizations have remained silent on the Tulsa massacre exposes the hypocrisy of the US' human rights claims, and highlights the deep-rooted discrimination against minority groups in the country.

The Tulsa genocide is a deep scar on the US. So before trying to assume the responsibility of safeguarding the human rights of people across the world, the US should first clean up its own house.

The author is a research fellow at the Institute of American Studies, the Chinese Academy of Social Sciences.

The views don't necessarily reflect those of China Daily.