At the same time, Kelly's comments about Dreamers were another reminder that the chief of staff shares some of Trump's instincts to insert tough language into polarizing issues.
The comment about Dreamers, uttered in the midst of difficult negotiations over how to prevent hundreds of thousands of new deportations, generated intense anger among Latinos and immigrant advocates.
Sen. Kamala Harris, D-Calif., said Kelly's "insults of Dreamers are both factually and morally wrong and do not speak to the best of who we are as a nation."
Rep. Luis Gutierrez, D-Ill., said on the House floor Thursday, "I say to the chief of staff of the president of the United States, the Dreamers are not lazy."
Kelly's taste for confrontation emerged in October as well, when he falsely accused a Democratic congresswoman, Florida Rep. Frederica Wilson, of grandstanding during the dedication of an FBI facility in Miami named for fallen agents.
Even when confronted with video evidence that his accusation wasn't true, Kelly refused to back down, displaying another Trumpian quality. The conflict with Wilson arose out of a dispute involving Trump's condolence call to the family of a fallen soldier.
Back then, the White House tried to insulate Kelly from criticism.
"If you want to get into a debate with a four-star Marine general," White House press secretary Sarah Huckabee Sanders said, "I think that that's something highly inappropriate."
During his time as a general, Kelly had a reputation as a forceful but pragmatic decision maker, said a former national security official who has worked closely with Kelly and now worries that his current post has clouded his judgment.
The attention to Kelly's actions has put him in an uncomfortable spot. In November, he explained part of his philosophy to reporters traveling with Trump to Asia. He insisted he was trying to push his staff away from the reactive mode that preceded his arrival.