Mr Gendron has been jailed without bail on a charge of first-degree murder. He pleaded not guilty.
“White supremacy is a poison. It’s a poison — it really is — running through our body politic,” said Mr Biden, who spoke moments after meeting with families of the victims as well as first-responders.
“We need to say as clearly and forcefully as we can that the ideology of white supremacy has no place in America. None.”
US Attorney General Merrick Garland and other Biden officials have called violence from white supremacists one of the biggest terrorism threats the United States faces, after related propaganda hit a record in 2020.
President Joe Biden visits the scene of the mass shooting at a Buffalo supermarket to pay respects and speak to families of the victimson Tuesday, 17 May, 2022. Source: Reuters / Andrew Harnik/AP
Investigators have said that they are looking into Mr Gendron’s online postings, which include a 180-page manifesto he is believed to have authored that outlines the “Great Replacement” conspiracy theory that white people were intentionally being replaced by minorities through immigration in the United States and elsewhere.
Mr Biden took aim at replacement theory, an idea with long historical roots in the United States that is surging through some conservative political circles now.
Mr Biden did not lay out specific blame. Fox News commentator Tucker Carlson was singled out by Democrats on Tuesday for allegedly stoking the theory in hundreds of episodes of his show. Mr Carlson has called the Buffalo shooter “immoral” and “crazy.”
Payton Gendron appears during his arraignment in Buffalo City Court, on Saturday, 14 May, 2022, in Buffalo, New York. Source: AAP / AP
“Hate and fear are being given too much oxygen by those who pretend to love America,” Mr Biden said, blaming politics and profits.
“Now is the time for the people of all races, from every background to speak up as a majority of America and reject white supremacy,” he said.
Mr Biden, joined by his wife, Jill, and a variety of New York political leaders stopped at a memorial set up under a tree to pay their respects near the supermarket where the gunfire rang out.
The scene in Buffalo was an all-too-familiar one for Mr Biden, who once again took up the role of consoler-in-chief. He said in his speech that he knew something about what the families of the fallen were going through, an apparent reference to the death of his son, Beau Biden.
Mr Biden reminded Americans that he ran for president to restore the soul of America, following predecessor Donald Trump’s failure to denounce a deadly white supremacist rally in Charlottesville, Virginia, and took office weeks after a deadly attack on the US Capitol that included racially motivated groups.
People attend a gathering to mourn for the victims of a mass shooting in Buffalo of New York State, the United States, 16 May, 2022. A heavily armed 18-year-old white man shot and killed 10 people and injured three others at a supermarket in Buffalo of New York State on Saturday. Credit: Xinhua News Agency/Xinhua News Agency via Getty Ima
But the Buffalo trip also showcased how little Mr Biden has achieved in stamping out a rise in white supremacist groups or curbing gun violence, with many Republican lawmakers blocking efforts to advance gun control measures and the country suffering a rash of mass shootings in recent months.
Mr Biden has asked Congress to require new background checks for gun buyers, and ban military-style “assault” weapons and large-capacity ammunition magazines.
But Democrats who largely support gun safety measures don’t have enough votes to pass them.
Mr Biden told reporters prior to leaving Buffalo that he realises it will be hard to get legislation passed.
A top FBI official told Congress in November that the bureau was conducting around 2,700 investigations related to domestic violent extremism, and the Department of Justice said in January it was creating a new unit to counter domestic terrorism.
