President Joe Biden's nominee for Secretary of Defense, Gen. Lloyd Austin, broke a barrier on Friday when he was sworn in as the first Black Pentagon chief in the nation's history.

The retired general officially took his position after senators voted 93-2 to confirm his nomination in a final floor vote, Forbes reported. Republican Sens. Josh Hawley of Missouri and Mike Lee of Utah were the only members to vote unfavorably. 

After being sworn in by Tom Muir, acting director of Washington Headquarters Services, Austin took part in an intelligence briefing and meetings with Deputy Defense Secretary David Norquist and Joint Chiefs of Staff Chairman Gen. Mark Milley. 

"It's an honor and a privilege to serve as our country's 28th Secretary of Defense, and I'm especially proud to be the first African American to hold the position," the trailblazer tweeted. "Let's get to work."

While the achievement was historic, there was also controversy that surrounded the nomination. The dissension revolved around a law that requires active duty service members to wait seven years before serving as defense secretary. Austin, who retired from the U.S. Army four years ago after 41 years of service, received a requisite waiver before taking his new position. A similar situation also took place four years ago when Congress issued a waiver for James Mattis, who was appointed by former President Donald Trump.

Some lawmakers are now displeased about granting the waiver yet again four years later. Senate Minority Leader Mitch McConnell, who is among the concerned officials, said the Senate should "pause and reflect" after granting both waivers.

"The law that we keep waiving actually exists for a good reason," McConnell said. "Civilian control of the military is a fundamental principle of our republic." 

The new beneficiary of the waiver tried to quell concerns during his confirmation hearing.

"Let me say at the outset that I understand and respect the reservations some of you have expressed about having another recently retired general at the head of the Department of Defense," Austin said. "The safety and security of our democracy demands competent civilian control of our armed forces, the subordination of military power to the civil."

The newly sworn-in secretary of defense also vowed to surround himself with qualified civilians to make policy decisions. But lawmakers pressed the general on the issue of extremism within the ranks of the military, a problem which is especially heightened after the Jan. 6 insurrection at the U.S. Capitol

"We woke up one day and discovered that we had extremist elements in our ranks and they did bad things," Austin said. "The signs for that activity were there all along. We just didn't know what to look for or what to pay attention to. But we learned from that."

During his four decades serving in the U.S. Army, Austin led military operations in Afghanistan, Iraq, Syria and Yemen, NPR reported. Sen. Dan Sullivan, who introduced the chief at his confirmation hearing, said he and Austin served together in the Middle East in 2005 and 2006. 

"I was just one of hundreds of field-grade infantry officers, recalled to active duty, deployed in the region during a challenging time for our nation," Sullivan said. "But when I asked for his time, Mr. Austin gave it. When I had a problem, he listened. And when I asked for help on an important mission, he provided it."

Majority Leader Chuck Schumer emphasized the significance of the historic moment that happened on the Senate floor. 

"Mr. Austin will be the first African American ever to helm the Defense Department in its history," Schumer said. "A powerful symbol of the diversity and history of America's armed forces."

Austin, a native of Mobile, Alabama, who grew up in Thomasville, Georgia, graduated from the U.S. Military Academy at West Point in 1975 with a commission in the infantry.