He was the U.S. Navy's "Old Goat" – the longest-serving Naval Academy graduate still on active duty – from January 2017 until April 2018, when he passed the title on to his classmate, Admiral Kurt W. Tidd, in a private ceremony at the Pentagon.

[11] He was also the Navy's 15th "Gray Owl" – the Naval Flight Officer on active duty who has held this designation the longest period.

[16] After his family's move to the United States, Harris grew up in Crossville, Tennessee, and Pensacola, Florida, where he attended local public schools.

Naval Forces Central Command / U.S. Fifth Fleet in Manama, Bahrain, serving as Assistant Chief of Staff for Operations, Plans, and Pol-Mil Affairs (N3/N5).

His educational assignments include selection for the Navy's Harvard/Tufts Program, where he graduated with a Master's of Public Administration from Harvard's John F. Kennedy School of Government in 1992.

His service was notable as he was in charge when three prisoners, Mani Shaman Turki al-Habardi Al-Utaybi, Salah Ali Abdullah Ahmed al-Salami and Yasser Talal Al Zahrani, died in the custody of US forces.

A report, Death in Camp Delta, was published in December 2009 by the Center for Policy & Research of Seton Hall University School of Law, under the supervision of its director, Professor Mark Denbeaux, attorney for two Guantanamo detainees, criticizing numerous inconsistencies in the official accounts of these deaths.

On January 18, 2010, Scott Horton of Harper's Magazine published a story suggesting that al-Salami, Al-Utaybi and Al-Zahrani had died as a result of accidental manslaughter during a torture session, and that the official account was a cover-up.

[23] Horton had undertaken a joint investigation with NBC News, based on an account by four former guards at Guantanamo Bay detention camp.

In November 2009, Harris assumed command of the U.S. 6th Fleet and the Striking and Support Forces NATO, both headquartered in Naples, Italy.

He regarded North Korea as the biggest threat to security in Asia, calling for diplomacy backed by military power to "bring Kim Jong-Un to his senses; not to his knees" in pursuit of peaceful denuclearization of the Korean Peninsula.

"[39] He called for the resurgence of the Quad -- the informal grouping of like-minded democracies of the U.S., Japan, Australian, and India -- at the inaugural Raisina Dialogue in New Delhi in 2016.

The tweet received criticism from the Korean press citing ROKG authorities’ comments that it was an inappropriate disclosure,[51][52] despite the purchase and delivery of the Global Hawk program having been part of the public record in both the United States [53][54] and Republic of Korea [55][56][57][58][59][60][61][62] since originally approved in 2012,[53] and the fact that his tweet was previewed with the ROK Ministry of Defense.

[63] He was awarded South Korea's Order of Diplomatic Service Merit (Gwanghwa Medal) at a ceremony in Washington, D.C. on September 8, 2021.

[64] Some South Korean activists criticized Harris over his mustache, which they claimed was reminiscent of Japanese-appointed Governors-General (Itō Hirobumi) during Japanese rule over Korea.

[67][68] A CNN article written by Joshua Berlinger suggested that given Harris's ancestry, the criticism of his mustache may be due to racism.

Harris referred to politicians around Moon Jae-in as "Jongbuk" (종북), and was later accused of acting like "Japanese colonial government" (일본 총독) by South Korean liberals.

In South Korea, the term "Jongbuk" is mainly recognized as an extreme right-wing rhetoric that ultra-conservatives use to criticize liberals and progressives.

[70] South Korean liberals and progressives generally support the Sunshine Policy, are skeptical of sanctions against North Korea, and are critical of Japan.

[77][78] Bruni Bradley is a 1984 Naval Academy graduate[79] and former Navy commander[80] who retired after 25 years of service and now is a member of the board of directors for the Military Child Education Coalition.