"The gun lobby simply won, you know?" Holder said in an interview with MSNBC's Melissa Harris-Perry which aired Sunday. In the interview, Holder reflected on his more than six years as the nation's top law enforcement officer.
Holder has called his visit to the site of the December 2012 massacre of 20 first-graders and six educators the worst day he had in office. In the aftermath of the shooting, President Obama appointed Vice President Joe Biden to lead a task force that would make recommendations for how to avoid such tragedies.
The shooting spurred an effort in the Senate to enact new, stricter gun laws, particularly a broader requirement for background checks for gun purchases proposed by Democratic Sen. Joe Manchin of West Virginia, a conservative with a strong gun-rights record, and Republican Sen. Patrick J. Toomey of Pennsylvania.
In part because of opposition from the National Rifle Assn., the Manchin-Toomey amendment fell five votes short of adoption, leading the Senate's Democratic leadership to abandon the underlying bill. With Republican majorities leading both the House and the Senate, new gun safety legislation is all but impossible on the federal level, although debates continue in some states.
A group of Democrats led by Sen. Robert Menendez (D-N.J.) and members of the Connecticut delegation introduced a bill Thursday to limit high-capacity magazines but said its passage would depend on a major public movement behind further gun control measures that has so far been lacking.
In the interview, Holder was asked if the United States was "a nation of cowards" when it comes to guns, a reference to a statement he made in 2009 that the U.S. was a nation of cowards when it came to discussing race relations.
"I don't think we are a nation of cowards. But I think that members of Congress need to have a little more backbone and stand up to what is a distinct minority even within, for instance, the N.R.A., and do the kinds of reasonable things that the American people simply want to have happen," he said.
In the interview, Holder downplayed what has been a largely hostile relationship with Republicans, calling his dealings with Congress "interesting" and claiming they had accomplished some things.
The nation has made "remarkable progress" on racial equality, he said, but he added that it was "extremely worrisome" that new restrictions on voting have been adopted 50 years after the Voting Rights Act.
"There have certainly been hits that the civil rights movement has taken, but nothing that I think can't ultimately be overcome," he said.
Holder will step down as attorney general upon confirmation of his successor. After a well-reviewed appearance before the Senate Judiciary Committee, Obama's nominee to replace him, Loretta Lynch, appears on track to be approved by March.
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