The White House is backing chief of staff John Kelly's defense of Confederate monuments and his assertion that the Civil War was caused by a failure to compromise.

White House Press Secretary Sarah Sanders told reporters Tuesday that Kelly's calling Confederate Gen. Robert E. Lee "an honorable man" was an attempt to point out that "history isn't perfect."

Sanders cited historian Shelby Foote to back up Kelly's claim that the "lack of an ability to compromise led to the Civil War."

Congressional Black Caucus Chair Rep. Cedric Richmond, D-La., criticized Kelly, saying he "needs a history lesson" for minimizing the role of slavery in bringing about the Civil War.

Kelly also said in an interview with Fox News host Laura Ingraham that aired Monday night that the removal of monuments to the Confederacy shows "a lack of appreciation of history." The retired Marine Corps general was responding to a question about a Virginia church's decision to remove historical markers for Lee and George Washington.

Kelly said that applying current thinking on social issues to figures in history is "very, very dangerous." He said the Civil War was sparked by "the lack of the ability to compromise."