[2] Upon completion of his tour with the Thunderbirds, he was assigned as an F-100 pilot with the 37th Tactical Fighter Wing at Phù Cát Air Base in South Vietnam.

On February 1, 1969, he was assigned to Project Commando Sabre (Detachment 1, 416th Tactical Fighter Squadron), known as the Misty FACs, a specialized group of high speed forward air controllers trying to stop vehicular resupply traffic down the Ho Chi Minh Trail.

He became the tenth commander of Commando Sabre on April 22, 1969, and moved it to the 31st Tactical Fighter Wing at Tuy Hoa Air Base on May 1, when the 37th TFW transitioned to the twin-seat F-4 Phantom II.

McPeak completed a total of 269 combat missions while in Vietnam, was awarded the Silver Star, and remained in-country until 1970, after which he attended the Armed Forces Staff College in Norfolk, Virginia.

McPeak was appointed Air Force Chief of Staff by President George H. W. Bush in October 1990, replacing the retiring General Michael Dugan following the latter's removal from the CSAF post by SECDEF Dick Cheney for ill-timed and inappropriate comments to the news media regarding Iraq during Operation Desert Shield.

In addition to a new three-button design with fewer and non-buttoning pockets, it changed the rank insignia for officers to use naval-style sleeve stripes, as opposed to metal pins on shoulder straps.

[6] McPeak also acted as Secretary of the Air Force for three weeks in 1993, before the formal appointment and confirmation of Sheila E. Widnall, becoming the only person to have ever concurrently served in both capacities.

[7][8][9][10][11] Some of this controversy may also be traced, at least in part, to the abrupt manner in which McPeak had replaced General Michael Dugan as Chief of Staff of the Air Force.

General Dugan, a popular and well-intentioned officer, had sought to repair the Air Force's image, badly frayed by the service's withholding of embarrassing information about the performance of the F-117 Nighthawk during the invasion of Panama.

Dugan had also sought to make top Air Force officials more accessible, but he was relieved of command by then-Secretary of Defense Dick Cheney shortly before the start of Operation Desert Storm and the first Gulf War following some intemperate remarks Dugan had made to the news media about targeting Iraqi leader Saddam Hussein under United Nations Security Council Resolution 666 prior to the start of hostilities, this despite the fact that as Air Force Chief of Staff, Dugan had no command authority within the U.S. Central Command theater of operations.

[14] In 2018, the government of France decorated McPeak (Legion of Honor, Officer class) in connection with his prior service as U.S. Air Force Chief of Staff and in recognition of his Chairmanship of the American Battle Monuments Commission (ABMC).

[citation needed] In May 2012, McPeak published Hangar Flying, the first volume of The Aerial View Trilogy, three memoirs that document his career in the Air Force.

[15] Goldberg begins the piece saying that "McPeak has a long history of criticizing Israel for not going back to the 1967 borders as part of any peace agreement with Arab states.

In 1976 McPeak wrote an article for Foreign Affairs magazine questioning Israel's insistence on holding on to the Golan Heights and parts of the West Bank.

"[15] Goldberg writes that "[in] recent years McPeak has echoed the Mearsheimer-Walt view that American Middle East policy is being controlled by Jews at the expense of America's interests in the region."

"[15] Goldberg also wrote that McPeak "claims that a combination of Jews and Christian Zionists are manipulating U.S. policy in Iraq in dangerous and radical ways.

"To support this claim, Goldberg quotes McPeak from a published interview: "Let's say that one of your abiding concerns is the security of Israel as opposed to a purely American self-interest, then it would make sense to build a dozen or so bases in Iraq.

"[20] According to journalist Allan Nairn, General McPeak oversaw the delivery of advanced U.S. fighter planes to Suharto's government not long after the November 1991 shooting of pro-independence demonstrators known as the Dili massacre.