Wednesday’s House Foreign Affairs Committee hearing entitled “Authorization for the Use of Force and Current Terrorist Threats” was the latest in a string of recent developments concerning efforts to replace the 2001 AUMF. Throughout the hearing, witnesses Michael Mukasey, former U.S. Attorney General, Brigadier General Rich Gross (Ret.), former legal counsel to the Chairman of the Joint Chiefs of Staff, and Matt Olsen, former director of the National Counterterrorism Center answered questions about the nearly 16-year-old law passed to target the 9/11 attackers and which now provides the domestic legal basis for military operations against numerous terrorist organizations in over half a dozen countries.

Here are a few key takeaways from the hearing:

1. The need for a new AUMF

Several committee members argued that a new AUMF was needed due to the extent the 2001 authorization has been stretched beyond congressional intent. “I was here when we passed this measure nearly sixteen years ago,” said Ranking Member Eliot Engel (D-NY), (who recently released an ISIS AUMF discussion draft) “and I have to say that none of us envisioned we would still be relying on it nearly two decades later to fight an enemy that didn’t even exist when the Twin Towers came down. It’s essentially become a blank check.”

Even those members who believe the 2001 AUMF provides sufficient domestic legal authority to fight ISIS agreed that it would be preferable to pass a new authorization, tailored to the current threat. As Committee Chair Ed Royce (R-CA) said, regardless of whether sufficient authority exists, “a new and updated authorization for the use of military force would be ideal.”

All three witnesses also said that a new authorization would be preferable. As Olsen explained, “it is clear that the 2001 AUMF is ill-suited to today’s threats,” also noting that the authorization’s “lack of time limits and reporting requirements, and the open-ended definition of who is covered, have undermined Congress’s ability to conduct effective oversight of the use of military force.” Mukasey remarked that the 2001 AUMF’s “authorization of force against those persons and entities responsible for the [9/11] attacks is likely inadequate and has necessitated the tracing of the lineage of current terrorist groups to al Qaeda and the Taliban.” And Gross said “it would be prudent for Congress to enact a new AUMF to specifically address the threat of ISIS and other terrorist groups,” to reflect the will of the American people, better define the mission, and “send an important signal of Congressional support to the U.S. Armed Forces.”

Given this agreement, the discussion focused less on whether Congress should work toward agreement on a new AUMF and more on what should be in it—particularly how to balance the need for Congressional authorization and oversight of military force with the need for flexibility in the face of a dynamic threat.

2. Clearly defining who is covered

The witnesses were in general agreement that to preserve Congress’ constitutional war-making powers and provide the military with clear authorities, a new AUMF should be specific about which groups it is authorizing force against, while maintaining flexibility to account for groups that may change their name or otherwise “rebrand.” As Olsen said in his written testimony, “The failure to carefully delineate the non-state entities subject to a statutory grant of authority for the use of force may lead to uncertainty and the kind of controversies that we have seen under the 2001 AUMF. This undermines Congress’ role in determining whom the country goes to war against and makes it more likely that wartime authorities to kill and detain will be used beyond their appropriate scope.”

Representative Scott Perry (R-PA) sparred with the witnesses about how broadly to define the enemy. In response to Perry asking about the effectiveness of his broad AUMF proposal, which he said authorized force against “Islamist extremism,” Olsen called this approach “overbroad,” saying that Perry’s formulation of identifying groups by “viewpoint” “would not be sustainable.” “I think it’s much safer to identify particular groups,” said Mukasey. Gross discussed the difficulties of advising a commander with an imprecise definition of the enemy. “I look at an authorization for use of force as a response to an enemy who has attacked us—an organized armed group,” said Gross.

3. Sunsets

The witnesses were repeatedly asked whether a sunset provision should be included in a new AUMF, with many members of Congress—on both sides of the aisle—agreeing on the merits of including a sunset. Both Mukasey and Olsen advocated in favor of sunsets, while Gross did not take a position. “As experts across the political spectrum have explained,” said Olsen, “a sunset does not end the war. Rather, a sunset signals to our partners and adversaries that the U.S. is committed to using the force required to combat the current threats we face, even as we sustain the fight for as long as it takes.”

Mukasey, who noted in his written statement that he does not generally favor sunsets in the intelligence gathering or counterterrorism authorities, advocated for a sunset in a new AUMF. “I favor a sunset provision,” he said. “I’ve favored reconsidering the [2001] AUMF for years.” Mukasey went on, “I think our enemies could misread [a sunset] unless we make the message explicit that the sunset provision is only to examine the way we focus our activities, and is not—and should not be read as—a limit on our commitment to oppose the forces that are fighting us.” He noted that other advantages of a sunset were that they “refocus and recommit people who were not around when the original AUMF was passed.” Gross said he agreed with Mukasey on the value of an AUMF sunset, which he said “sets a date certain when…the President and Executive Branch and the Congress–will know the deadline is coming up and begin to reexamine [the AUMF.]” He also noted that some operational considerations may arise with a sunset, saying “I think the negative consequences are…[i]t does create a lot of legal uncertainty as you approach that deadline…There’s a lot of uncertainty with whatever military operations are ongoing at that time and whatever detention operations are going on at that time.”

Representative Dana Rohrabacher (R-CA) was one of the most forceful proponents of sunsets. Rohrabacher called an AUMF sunset “a commitment to get the job done in a timely manner.” “[W]e aren’t limiting the commitment,” he continued. “We’re just telling people if you’ve got a commitment to military action you’ve got to get it done and that this isn’t just going to linger forever.” Rohrabacher went on to discuss how a sunset could have been beneficial for oversight of the Vietnam War, noting “it would’ve been a good thing for us to have to reevaluate after four or five years that whole Gulf of Tonkin resolution.”

4. The issue of ground troops remains a sticking point

In discussing the issue of including restrictions on ground troops in a new AUMF, Olsen noted that the “declare war” power that resides with Congress includes the authority to decide what kind of force to authorize. In Olsen’s written testimony he stated: “Legally, some mistakenly assume that Congress simply does not have the constitutional authority to limit the use of ground troops. Neither the history of past war authorizations nor U.S. case law supports this view.” Olsen went on to state that “as the representatives of the American people, Congress has an extraordinarily important role to speak for the American people and impose appropriate restrictions on how…force is exercised.”

Gross, on the other hand, said that terms like “no boots on the ground” or “no enduring large-scale combat” could “restrict the ability of the president and military commanders to plan…and [] might take options off the table that they needed” and Mukasey commented that “micromanaging any combat is a dangerous thing.”

5. War is not—and cannot—be the only tool to counter terrorism

Representative Barbara Lee (D-CA), who while not on the committee, has been very active on this issue and was given permission to attend the hearing. Lee asked the witnesses their views on the roles of other government agencies and departments in protecting the United States from the terrorist threats.

Olsen and Gross discussed the necessity for a whole-of-government approach to effectively combat terrorism. “I think that’s something that everyone I served with over two administrations—Republican and Democrat—agreed with,” said Olsen, noting that Secretary of Defense Jim Mattis also considers that “the use of force [should be] a last resort in our counterterrorism fight.” “I couldn’t agree more,” said Gross “[A]ll the elements of national power ought to be brought to bear and the military ought to be the last resort.” “We need diplomacy to work.”

Closed Senate Hearing with Tillerson and Mattis Next Week

Next Wednesday, the Senate Foreign Relations Committee plans to hold a hearing with Secretaries Mattis and Tillerson to discuss “The Authorizations for the Use of Military Force: Administration Perspective.” The executive branch’s views on the extent to which military force is currently needed to supplement other counterterrorism efforts is key to Congress determining what authorities to provide.

But holding the hearing in an entirely closed session is undemocratic and unnecessary. Hearings on national security matters are routinely held in public—including several prior AUMF hearings before the same committee, featuring the same officials. Closed sessions certainly have their place. But for proper transparency, these should be conducted as well as—not instead of—hearings that are open to the American public that Congress represents.

One thing is clear: the AUMF discussion that was dormant in Congress for so long is continuing to pick up speed. “I think it could be done,” said Representative Ron DeSantis (R-FL) in Wednesday’s hearing. “I think it would actually be one of the few times we actually have an insightful debate on the House floor for a change.” With increasing congressional engagement, several members releasing AUMF proposals, and now the executive branch about to weigh in, there is certainly more to come on this issue.