Chairman of the Joint Chiefs Gen. Mark Milley told lawmakers Thursday that climate change is a serious threat facing the United States -- one that the military must take into account.
Milley's comments came a day after President Joe Biden told U.S. troops in England that top military leaders had told him about 12 years ago that global warming was the greatest threat facing America, due to its effects on population movements, increased scarcity of land capable of growing food and possible fighting over land.
"When I was over in the Tank in the Pentagon, when I first was elected vice president with President Obama, the military sat us down to let us know what the greatest threats facing America were -- the greatest physical threats," Biden said at RAF Mildenhall. "And this is not a joke: You know what the Joint Chiefs told us the greatest threat facing America was? Global warming."
During a Senate Armed Services Committee hearing to discuss the Pentagon's proposed fiscal 2022 budget, Milley said that China is the top military threat facing the United States, and Russia is also a considerable "great power competitor."
Sen. Kevin Cramer, R-N.D., asked Milley about Biden's comments about global warming being America's greatest threat.
Milley replied that climate change has had a significant effect on military operations that must be considered.
"Climate change is going to impact natural resources, for example," he said. "It's going to impact increased instability in various parts of the world. It's going to impact migrations, and so on."
Milley also cited the effect hurricanes -- which scientists say have been worsened by warming oceans -- have had on infrastructure in the United States. Tyndall Air Force Base in Florida was devastated by a major hurricane in October 2018.
He said there is no difference of opinion between himself and Biden when it comes to taking climate change as a serious threat.
"The president is looking at [potential threats] at a much broader angle than I am," Milley said. "I'm looking at it from a strictly military standpoint and, from a strictly military standpoint, I'm putting China and Russia up there. That is not, however, in conflict with the acknowledgment that climate change, or infrastructure, or education systems -- national security has a broad angle to it."
The Biden administration's first proposed Pentagon budget, released late last month, called climate change a "national security priority" and asked for $617 million in new infrastructure investments to help prepare for and respond to climate change.
During the hearing, Milley also addressed sexual assault and harassment in the ranks, saying "some significant and fundamental change" to how the military prosecutes such crimes is needed.
He was responding to a question from Sen. Kirsten Gillibrand, D-N.Y., who asked him to confirm reports that he is open to removing the authority to prosecute sexual assault and related crimes from the chain of command.
Milley replied that he is "completely open-minded" to significant changes for those offenses, adding that most of the military's other senior leaders feel the same.
Gillibrand said she has proposed "draw[ing] a bright line at all serious crimes" in the military and taking those prosecutions out of the chain of command, which she said would increase transparency and accountability in the system and lessen bias.
Gillibrand's proposals, which she has backed for eight years, instead would give military attorneys the decision on whether to prosecute in cases of serious crimes, such as sexual assault, murder and child pornography.
But Milley indicated he is not yet willing to make similar changes to the Uniform Code of Military Justice, or UCMJ, for other felonies, saying more study would be needed first.
"It needs a lot of due diligence before we bundle all the ... felonies and take them away from the commander," he said.
Milley's comments Thursday show a continued thaw in his once-staunch opposition to changing how the military prosecutes sexual assaults. Last month, he told The Associated Press that he had dropped his opposition to suggestions -- backed in a slate of initial proposals from an independent review panel studying sexual assault in the military -- to no longer have commanders make decisions on whether to prosecute sexual assault cases.
He told the AP in May that "I was adamantly opposed to that [proposal] for years," but the military's ongoing failure to stop sexual assault had prompted him to reconsider his position.
During the hearing, Milley said that sexual assault and other offenses are not just crimes, but threats to military units' ability to effectively accomplish their missions.
Unit cohesion is one of the greatest factors contributing to the military's effectiveness, he said, and sexual assault, sexual harassment or "any kind of deviance from any sort of good order and discipline" tears that cohesion apart.
Commanders are also personally responsible and accountable for their units' good order and discipline, Milley said.
"I am absolutely open-minded to suggestions to improve the system, because what we want to do is fix the problem and improve the combat power of the U.S. military," he said.
During the hearing, Defense Secretary Lloyd Austin said he also is willing to make such changes, adding that he is awaiting additional recommendations for the Pentagon's independent review commission.
Sen. Thom Tillis, R-N.C., expressed concerns to Austin that the sweeping changes to the UCMJ backed by Gillibrand would take significant time and effort. Austin replied that the Pentagon will need "ample time" to properly enact any UCMJ changes.
Lawmakers also asked Austin about the military's effort to withdraw troops from Afghanistan, which is now more than halfway completed.
Austin said that the military is already carrying out some missions, such as combat missions or intelligence, surveillance and reconnaissance flights, from outside Afghanistan. MQ-9 Reaper drones are some of the aircraft conducting ISR operations in Afghanistan while operating from elsewhere in the region.
But he acknowledged that once all U.S. personnel, except a handful of troops to guard the U.S. Embassy in Kabul, are gone, supporting Afghan security forces "will be very difficult to do."
Austin said the military's effort to station assets in countries neighboring Afghanistan to conduct so-called over the horizon counterterrorism missions is still a "work in progress," though he could not say when that might be ready.
He declined to comment on a New York Times report that the military is considering whether to conduct airstrikes to support Afghan security forces if there is a danger of the Taliban overrunning Kabul or other major cities.
"I won't speculate about any potential outcomes or any potential future actions," Austin said. "I will just say that the president has been clear that our mission in Afghanistan has been accomplished, and we are focused on retrograding our people and equipment out. And going forward, those [counterterrorism] efforts will be focused on those elements that can possibly conduct attacks against our homeland."