Former Vice President Joe Biden slammed President Trump in a new op-ed, accusing the president of misunderstanding and misrepresenting American values in a way no president has done since the Jim Crow era.

In an op-ed for the New York Times published Thursday, Biden criticized the president's treatment of U.S. allies like Germany, his comments on the violence in Charlottesville, Va., and the administration's announcement that it will rescind Deferred Action for Childhood Arrivals.

"Mr. Trump's shameful defense of the white nationalists and neo-Nazis who unleashed hatred and violence in Charlottesville, Va., further abnegated America's moral leadership," Biden wrote of the president's remarks on last month's events in Charlottesville. "Not since the Jim Crow era has an American president so misunderstood and misrepresented our values."

In initial comments after white nationalists clashed with counter-protesters in Charlottesville on Aug. 12, Trump failed to specifically denounce the white nationalist groups who were protesting there. He did so two days later in prepared remarks, but reverted to his initial comments that "both sides" were to blame for the violence in a press conference the following day.

In his op-ed, Biden lamented the president's decision to keep Germany at a distance while "expressing admiration" for Russian President Vladimir Putin.

"Rather than building from a narrative of freedom and democracy that inspires nations to rally together, this White House casts global affairs as a zero-sum competition — for the United States to succeed, others must lose," Biden wrote. "Among the many problems that plague the Trump administration's foreign policy, this line of thinking is perhaps the most disturbing."

Biden, who has a new book due out in November, also warned the U.S. risks losing its standing in the world if it abandons its values, including "inclusivity, tolerance, diversity, respect for the rule of law, freedom of speech, freedom of the press."

"You cannot define Americans by what they look like, where they come from, whom they love or how they worship," he said. "Only our democratic values define us. And if we lose sight of this in our conduct at home or abroad, we jeopardize the respect that has made the United States the greatest nation on earth."