WASHINGTON — President-elect Donald Trump’s choice for defense secretary, Pete Hegseth, vowed Tuesday to foster a “warrior culture” at the Pentagon and confronted allegations of sexual assault and excessive drinking and questions about his derisive views of women in combat during a heated Senate confirmation hearing.

Hegseth repeatedly deflected the various misconduct allegations and instead focused on his own combat experience in the Army National Guard as senators determine whether the combat veteran and former TV news show host is fit to lead the U.S. military.

“It’s time to give someone with dust on his boots the helm. A change agent,” Hegseth said in his opening remarks.

Asked directly about the sexual assault allegation, Hegseth dismissed it as a “smear campaign,” as he did in response to a rapid-fire series of questions about his personal behavior and complaints of drinking on the job. He has vowed not to drink alcohol if he is confirmed to lead the Pentagon. But pressed about his marital infidelity, Hegseth acknowledged, “I am not a perfect person.”

Senators spent hours probing the concerns surrounding Hegseth, with the Republican chairman of the Senate Armed Services Committee acknowledging the “unconventional” choice. But Sen. Roger Wicker, R-Miss., compared Hegseth to Trump himself, and said he will “bring energy and fresh ideas to shake up the bureaucracy.”

The top Democrat, Sen. Jack Reed of Rhode Island, however, called the allegations “extremely alarming” and said flatly: “I do not believe that you are qualified to meet the overwhelming demands of this job.”

Hegseth, 44, comes from a new generation of veterans from the Iraq and Afghanistan wars, and his military experience is widely viewed as an asset. But he also brings a jarring record of past actions and statements, including about women, minorities and “woke” generals.

Hegseth also does not have the credentials typical of a defense secretary, raising questions about his ability to manage an organization with nearly 2.1 million service members, about 780,000 civilians and a budget of roughly $850 billion.

The more than four-hour hearing launched a weeklong marathon as the Republican-led Senate is rushing to have some of Trump’s nominees ready to be confirmed as soon as Inauguration Day, Jan. 20. With a narrow GOP majority, almost all Republicans must support Trump’s pick if Democrats oppose.

Hegseth faces perhaps the most difficult path to confirmation, but GOP allies are determined to turn him into a cause célèbre for Trump’s governing approach amid the nation’s culture wars. Outside groups, including those aligned with the Heritage Foundation, are running costly campaigns to prop up Hegseth’s bid.

In the audience were cadres of men wearing clothing expressing support for veterans or service in the military, but also protesters who momentarily disrupted proceedings but were removed from the room.

Hegseth was combative at times, as he was forced to confront the allegations of misconduct and his own comments that are far from the military mainstream.

Pressed on his opposition to diversity initiatives, Hegseth agreed that the military “was a forerunner in courageous racial integration.” But he argued that modern diversity and inclusion policies “divide” current troops and don’t prioritize “meritocracy.”

In a striking scene, several female Democratic senators grilled Hegseth over his comments that women should “straight up” not be in combat roles, a view he has softened since his nomination.

Sen. Jeanne Shaheen, D-N.H., noted the switch. “Which is it?”

In one fiery exchange, Sen. Kristen Gillibrand, D-N.Y., told Hegseth: “You will have to change how you see women to do this job.”

And Sen. Tammy Duckworth, D-Ill., who lost both legs when the Blackhawk helicopter she was piloting was shot down, displayed the Soldier’s Creed she said hung at her hospital bed and by which all Army service members are expected to live. She told the nominee the troops “cannot be led by someone who is not competent.”