The only time I ever met Robert Swan Mueller III did not go over too well with his security detail.

This was in 2001 as Mueller faced his confirmation hearing before the Senate Judiciary Committee to become FBI Director. There was milling about before the hearing started. Mueller was at the back of the room huddled with aides and the passing senator or two who stopped to greet him.

I was a reporter covering the hearing. I approached and for whatever reason blurted out "Hey, you Magnificent Bastard," or maybe just "Hey Bastard," which was sometimes how members of the 2nd Battalion, 4th Marines, greeted each other. Members of 2/4 have officially been dubbed "Magnificent Bastards" since 1964, and origins of the term possibly go back to World War II.

The intense, and large, denizens of the security detail with Mueller began to close on this approaching fool with a pencil and a notebook. Mueller, as I recall, also looked surprised and then laughed. We shook hands.

He asked what company I was with. I said "Fox," but told him that I was gone before he arrived in Vietnam in the summer of 1968. He said he was with "Hotel," and that was it.

I may have asked Mueller a question at some point in his 12 years as FBI Director -- I don't remember -- but that was our only contact.

Some members of my platoon in Fox 2/4 kept in touch after I left -- I had been wounded for the second time in June 1968 -- and they occasionally mentioned the curious new lieutenant in Hotel Co. They said he was Ivy League, which they thought strange -- nobody from an Ivy League school went to Vietnam.

What was even stranger -- he didn't curse, at least in front of them -- and that was decidedly uncommon for a Marine. They also said that he was "solid," and knew how to listen. And they also liked that he was a "Mustang" -- he had enlisted out of Princeton and gone through Parris Island boot camp just like them, and then through Officer Candidate School.

Mueller would earn the Bronze Star, the Purple Heart and the Vietnamese Cross of Gallantry in his time in Vietnam. The citation for his Bronze Star said that during an attack on his rifle platoon, "2nd Lt. Mueller fearlessly moved from one position to another, directing the accurate counterfire of his men and shouting words of encouragement to them."

During the firefight on Dec. 11, 1968, Mueller "personally led a fire team across the fire-swept terrain to recover a mortally wounded Marine who had fallen in a position forward of the friendly lines," the citation said.

In May 2017, Mueller was named by Deputy Attorney General Rod Rosenstein to serve as Special Counsel for the Justice Department.

As Special Counsel, Mueller was directed to investigate "any links and/or coordination between Russian government and individuals associated with the campaign of President Donald Trump, and any matters that arose or may arise directly from the investigation."

Mueller has rarely spoken of his time in the Marines or how he came to join but at Princeton, he was on the lacrosse team with David Spencer Hackett. Hackett joined the Marines and served as a lieutenant in Vietnam, where he was killed by small arms fire in 1967.

In a 2013 commencement speech at the College of William and Mary, first reported by Jeff Schogol of Marine Times, Mueller recalled the death of his friend and how that led him to the Marines.

"One would have thought that the life of a Marine, and David's death in Vietnam, would argue strongly against following in his footsteps," Mueller said.

"But many of us saw in him the person we wanted to be, even before his death. He was a leader and a role model on the fields of Princeton. He was a leader and a role model on the fields of battle as well. And a number of his friends and teammates joined the Marine Corps because of him, as did I."

"I do consider myself fortunate to have survived my tour in Vietnam," Mueller said. "There were many -- men such as David Hackett -- who did not. And perhaps because of that, I have always felt compelled to try to give back in some way."

When his Special Counsel job ends, maybe Mueller can use his investigating skills to learn the true origin of the term "Magnificent Bastards" for 2/4. There are conflicting versions of how it came about.

One has it that there was a tough fight on a Pacific Island but word got back to the ships that 2/4 had broken through enemy lines. Somebody on the ships said "Oh, you magnificent bastards" and the name stuck.

Another has it that there was a change of command ceremony for 2/4 and a couple of Marines bumped into each other during the pass in review, precipitating a mass brawl on the parade field.

The new commander was delighted and called them a bunch of "Magnificent Bastards." In 1964, Lt. Col. J.R. "Bull" Fisher added "Magnificent Bastards" to 2/4's insignia.

-- Richard Sisk can be reached at Richard.Sisk@Military.com.