Marine Corps Commandant Gen. James Amos made the call on Monday, marking the first time since the Vietnam War a top American general was relieved of command due to failures on the battlefield.
The attack was "was a tragic example of the horror of war" and represented the tough fight facing Marine Corps units in Southern Afghanistan.
That said, Amos' decision reinforces the service's effort to "maintain accountability" among its commanders, even in the face of the dangerous mission being carried out by Marines in Afghanistan, according to McCain.
"We owe it to those who lost their lives and their families to learn from this event and do all that is necessary to protect in the future our servicemen and -women serving in forward areas," the Arizona Republican added.
Prior to his dismissal, Gurganus was nominated to be promoted to Lieutenant General has been rescinded. That nomination before the Senate Armed Services Committee was rescinded while Sturdevant was given an official letter of reprimand by Navy Secretary Ray Mabus.
"The Commandant has asked both generals, in spite of long and distinguished careers, to retire," according to a Marine Corps statement issued Monday.
Several Taliban gunmen, wearing U.S. Army uniforms, launched a daring suicide attack against Camp Bastion, the United Kingdom's largest military outpost in southern Afghanistan in September 2012.
American and NATO troops were able to kill all but one of the attackers and repel the Taliban assault, but not before the attackers were able to overrun the base's outer perimeter and destroy six AV-8B Harrier fighter jets stationed at Bastion.
Gurganus, who was the top service commander in the region at the time of the attack, “failed to exercise the level of judgment expected of commanders of their rank,” Amos said in the statement.
The three-star general, "made an error in judgment when conducting his risk assessment of the enemy’s capabilities and intentions" during his time in command at the UK-run Camp Bastion and the adjoining Marine Corps base, dubbed Camp Leatherneck.
Even though Bastion was under British command, Sturdevant "remained responsible for assessing vulnerabilities" to the service fighter jets stationed at U.K. forward operating base.
Sturdevant was the Corps' senior aviation officer at Bastion and Leatherneck at the time of the attack.
“Marines can never place complete reliance for their own safety in the hands of another force,” Amos said.