By Phil Stewart and Idrees Ali
WASHINGTON (Reuters) - Ash Carter, who served as a U.S. defense secretary during the Obama administration, died late on Monday at the age of 68 after a sudden cardiac event, his family said in a statement on Tuesday.
A decades-long defense wonk who gradually ascended to the Pentagon's top job, Carter helped oversee the launch of a military strategy that would drive back the Islamic State in Syria and Iraq, and ultimately defeat the militant group.
Under Carter, the U.S. military opened all military roles to women and also ended a ban on openly serving transgender service members. He strongly criticized then-President Donald Trump's decision in 2017 to reimpose the ban.
"To choose service members on other grounds than military qualifications is social policy and has no place in our military," Carter said at the time.
Before becoming defense secretary in 2015, Carter served as deputy defense secretary and chief operating officer in the Pentagon. He also oversaw the Defense Department's weapons purchases from 2009 to 2011 when he led a major restructuring of the F-35 fighter jet program.
"Carter always set politics aside; he served presidents of both parties over five administrations, holding multiple positions within the Department of Defense," his family said in the statement.
Carter held a doctorate in theoretical physics from Oxford University, and on at least one occasion overseas even spoke to the media about black holes. Inside the Pentagon, he was seen more as a technocrat than a politician.
He tried, with limited success, to bridge a gaping divide between the Pentagon and Silicon Valley to bring technological innovations to the Defense Department more quickly.
President Joe Biden said in a statement that Carter was a "man of extraordinary integrity."
"Above all, Ash understood the sacred obligation we have to our servicemembers, veterans, and their families," Biden said.
Former Defense Secretary Robert Gates said in a statement that Carter's (NYSE:CRI) "insights and perspectives will be difficult to replace and his humor and regard for the troops deeply missed."
Former President Barack Obama said he used to rely on Carter's counsel for making the military "stronger, smarter, more humane, and more effective."
"Ash's greatest legacy, however, may be the generations of younger leaders he taught, mentored, and inspired to protect our nation and wield power wisely," Obama said in a statement.
Since leaving public service, Carter led the Belfer Center for Science and International Affairs at Harvard's Kennedy School.
He is survived by his wife, Stephanie, and his children, Ava and Will.