Washington DC - President Donald Trump on Wednesday nominated a Secret Service agent who rushed onstage to protect him from a would-be gunman during a failed election rally assassination bid to become the agency's next director.

Sean Curran, the head of Trump's personal security detail, was among several agents who surrounded Trump as a gunman in Butler, Pennsylvania, opened fire on the then-candidate, leaving him with a bloodied ear.

He was identified by US media as the man in sunglasses to the right of Trump in a series of iconic photos showing the Republican raising a defiant fist as he is escorted offstage with blood trickling down his face.

The nomination flies in the face of a review of Secret Service failures following the attack, which recommended looking to someone with a wealth of experience outside the organization for its next leader.

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"Sean is a Great Patriot, who has protected my family over the past few years, and that is why I trust him to lead the Brave Men and Women of the United States Secret Service," Trump posted on his website, Truth Social.

The president noted Curran's 23-year Secret Service career that began when he was a special agent in the Newark field office and led to his promotion to become head of the Presidential Protective Division in the Republican's first term.

"He proved his fearless courage when he risked his own life to help save mine from an assassin's bullet in Butler, Pennsylvania," Trump said.

"I have complete and total confidence in Sean to make the United States Secret Service stronger than ever before."

The appointment had been expected, with the president's son, Donald Trump Jr., announcing as long ago as last week that the "great patriot" would be getting the job.