For nearly two decades, this day has been a solemn one, dedicated to remembering those we lost in the terrorist attacks of September 11, 2001. It’s a day to remember the sense of national unity we felt around a common purpose after 9/11. During my years in government, it was a day when we gathered to remember how 9/11 drew so many of us into public service and to remind ourselves of the noble mission we had the privilege to carry out. I will spend time today reflecting on all of this and hopefully emerge with a renewed sense of purpose.

But as the pain and trauma of that day has receded in recent years, the anniversary of 9/11 has also become a reminder of a fact we would have found inconceivable at the time: that we continue to wage war some two decades later. A war that started out with relatively clear aims against specific enemies has long since morphed into a “Forever War,” comprising a diverse range of conflicts, most of which are only tenuously tied to the attacks of 9/11 and the original response to them against al-Qaeda and the Taliban.

This year, with COVID-19 soon to claim its 200,000th American victim, questions about why we’re still dedicating so many resources to fighting overseas terrorist groups are rendered particularly stark. Calls across the political spectrum to end the Forever War, already loud in an election year, have only been amplified. Yet resolving to end endless wars is easier than actually concluding them. Experts have noted the complexity and risk of withdrawing from key theaters and have emphasized the need for continued U.S. military presence – or slowly phased drawdowns – in Afghanistan, Iraq, Syria, and elsewhere as a check against the resurgence of al-Qaeda and ISIS.

Determining how to end the Forever War will likely be a top foreign policy priority in the coming months, regardless of who wins the White House. The U.S. counterterrorism campaign has gone through many evolutions over the past 19 years, but several core assumptions about the enemy, our ability to defend against attacks, and the offensive actions necessary to degrade terrorist groups remain largely unchanged. There is a lot we don’t know and there are risks to every decision; risks of over-investing in counterterrorism and underinvesting in something else, risks of the opposite. But as we contemplate our future policy decisions, we must weigh the facts and examine our assumptions closely. A good start would be to ask (and think carefully through) at least five key questions:

Is it safe to play defense?

Since 9/11, we have operated on the assumption that if terrorists are allowed to plot without consistent offensive military pressure from the United States and its partners, they will develop the capabilities to strike the U.S. homeland and carry out additional high-profile attacks. Yet this assumption began before we made massive investments in our defenses that make any terrorist plot far less likely to succeed. We have created an entire federal department focused on protecting our borders, infrastructure, and aviation system from terrorism and other threats. The Intelligence Community has grown dramatically its counterterrorism capabilities and created an agency (the National Counterterrorism Center) that is exclusively focused on counterterrorism. The FBI reorganized itself to place counterterrorism at the center of its mission. State and local governments have extensive counterterrorism capabilities and work closely with federal partners to prevent attacks. Overseas, the United States has invested in partnerships and multilateral institutions designed to deprive terrorists of funding, detect terrorist plotting, prevent the flow of foreign terrorist fighters across borders, and deny terrorists the ability to obtain the materiel they need to conduct attacks. International cooperation has greatly reduced terrorists’ ability to develop weapons of mass destruction, especially nuclear devices. In short, we have created a large, effective apparatus to detect and defend against terrorist attacks.

Of course, no defense can be 100 percent effective, but the question is whether playing defense makes us safe enough. Can we trust this apparatus to defend the nation to the point where only sporadic small attacks – the kind that a resilient nation can easily recover from – are possible? Or do we need to continue applying military pressure on a broad range of terrorist groups that threaten or aspire to threaten the United States? If the answer is that substantial offensive pressure remains essential, then can we scale back some of our massive investments in homeland security and intelligence? A combined homeland security and offensive overseas campaign that has cost us between $3-6 trillion over 20 years cannot be sustained at that level indefinitely.

What is the impact of so many dead terrorist leaders?

Of the things the United States has done well since 9/11, killing terrorist leaders has to be near the top. The United States has killed al-Qaeda leader Osama bin Laden, ISIS leader Abu Bakr al-Baghdadi, al-Qaeda in Iraq leader Abu Musab al-Zarqawi, al-Shabaab leader Ahmed Abdi Godane, and countless deputies, operational commanders, and others in targeted strikes. Still more have been captured. Obama administration officials touted these wins, claiming that al-Qaeda’s leadership was “decimated” through the elimination of leaders in rapid succession. The Trump administration has similarly hailed its successful missions. Although some key terrorist leaders, including longtime al-Qaeda leader Ayman al-Zawahiri, remain at large, these are the exception rather than the rule, as the United States has made clear that it can target and kill or capture virtually any terrorist leader in the world.

Yet for all of these gains, it seems that after every removal of a top terrorist, the Intelligence Community assesses that the threat remains and that continued offensive action is necessary. After Baghdadi’s death late last year, U.S. Central Command and the Defense Intelligence Agency assessed that, “the October death of al-Baghdadi did not result in any immediate degradation to ISIS’s capabilities.” The Department of Defense has assessed that absent sustained counterterrorism pressure, ISIS would regenerate itself in 6-12 months. Retired CIA officer Doug London argues in Just Security today that absent sustained counterterrorism pressure, al-Qaeda and other terrorist elements will regenerate in Afghanistan.

If the entire top tiers of leadership and technical expertise of a major U.S. economic industry were removed, we would assume that it might take many years to regenerate the expertise, experience, and organization necessary to resume normal operations. Yet with terrorism – where our strikes have not only caused organizational harm but inflicted great fear and trauma in our enemies – the assessment is often that if we don’t maintain a steady pace of strikes against terrorists, the threat will return with a vengeance in a relatively short period of time. There are still other questions to consider when it comes to targeted killing – such as whether strikes (particularly those that cause civilian casualties) are significant drivers of terrorist recruitment, or whether terrorists killed or captured (especially those held at Guantanamo Bay) become martyrs who motivate their erstwhile followers to greater action. If the answers are, indeed, that terrorists can still easily regenerate capabilities, and that the counterproductive elements of our strikes are substantial, then we must ask whether our strategy of leadership removal has been the right one in the first place or whether other efforts would make more of a dent in reducing the threat.

Does al-Qaeda or ISIS affiliation matter?

In early 2014, while discussing the threat from ISIS as compared to al-Qaeda, President Barack Obama told The New Yorker

if a jayvee team puts on Lakers uniforms that doesn’t make them Kobe Bryant…I think there is a distinction between the capacity and reach of a bin Laden and a network that is actively planning major terrorist plots against the homeland versus jihadists who are engaged in various local power struggles and disputes, often sectarian.

Obama was roundly criticized when just a few months later, ISIS seized Mosul in Iraq and large parts of northeastern Syria and quickly became the most serious terrorist threat we have faced since 9/11. He had publicly downplayed the threat, and in the eyes of his critics, that meant he did not take it seriously enough or do enough to prevent it. Yet, while Obama was wrong about ISIS in early 2014, he raised a good point about the nature of the global jihadist movement. Since 9/11, we have expressed concern about the proliferation of al-Qaeda and ISIS affiliates, even when they pose a limited threat to the U.S. homeland. Central to ISIS’s strategy has been the rapid proliferation of more than a dozen “provinces,” stretching from the North Caucasus to the Democratic Republic of the Congo. Although some of these provinces, most notably ISIS’s affiliate in Libya, have presented a concerning threat to U.S. and regional security, most have been little more than criminal militias, posing an isolated regional threat. Al-Qaeda is more discerning about which groups it admits as affiliates, but even it boasts affiliates in far-flung locations with tenuous ties to the central organization.

Within the United States, nearly all terrorist attacks attributable to Islamist terrorists have been carried out by homegrown violent extremists, the vast majority of whom could not claim any real tie to ISIS or al-Qaeda beyond consuming their propaganda.

To be sure, the United States does not target every ISIS or al-Qaeda affiliate, nor does it treat them all as equal threats. But policymakers tend to focus heavily on questions of what makes a group an affiliate or associated force of al-Qaeda, and national security officials are quick to point to a sprawling web of terrorist groups to highlight the overall threat we face or to justify security assistance or other counterterrorism programming. So, the question for policymakers is: How much does it matter for any given group to be part of the ISIS or al-Qaeda global network? Does membership confer certain benefits or suggest the possibility of catastrophic attacks if left unchecked? Is there an alternative where the United States might focus on the handful of affiliates that pose the greatest threat and treat others as actual nodes in a terrorist network only if they significantly contribute to the core group?

How much should we focus on small-scale attacks?

Well before 9/11, the world faced periodic small-scale terrorist attacks, but it was the catastrophic nature of the 9/11 attacks that changed everything. The counterterrorism infrastructure that the United States built after 9/11 was focused on preventing the next big terrorist attack – whether on an iconic piece of infrastructure, commercial aviation, a major event, or some other high-profile target. For its part, al-Qaeda eschewed small-scale attacks, instead focusing its efforts on high-profile attacks like the failed 2006 aviation plots. But with the rise of al-Qaeda in the Arabian Peninsula, and especially with ISIS, terrorist leaders began to focus on a new model of inspiring homegrown violent extremists to conduct attacks and providing them with basic instruction on how to successfully do so. At ISIS’s peak, in 2014 to 2016, the group seemed to be presiding over a steady tempo of small-scale attacks that, while not inflicting anything near the destruction of 9/11, threatened to inflict large amounts of terror through their sheer unpredictability and rapid pace. Since then, the pace of small-scale terrorist attacks has decreased substantially, as ISIS has lost ground and momentum and suffered the death of its top propagandist. At home, the FBI and local law enforcement have made major gains in preventing such attacks, and the leading social media companies have moved to restrict the spread of terrorist propaganda and instructional materials enabling violence.

From a purely strategic perspective, U.S. officials should ask what the threat of small-scale attacks looks like today and whether, by virtue of their scale, tempo, or other measures of severity, they pose a threat that merits significant overseas military operations. Of course, we’ll need to continue to address terrorism in the homeland – whether directed, inspired, or self-motivated – through a mix of law enforcement and countering violent extremism programming. And it will be almost exclusively domestic law enforcement that’s charged with preventing domestic terrorists, particularly those motivated by far-right ideologies, from carrying out political violence and terrorism. But as we survey the range of overseas threats, policymakers should be asking what types of threats we face from leading terrorist groups and whether any approximate the capabilities that drove us into this conflict in the first place.

Is resilience possible?

Beyond the strategic question of how to address small attacks is a political question. U.S. officials and the media still too often hype the threat of any attack. As former Obama Deputy National Security Advisor Ben Rhodes has explained, terrorism has become deeply ingrained in our political media culture, such that even the smallest of attacks or threats are amplified and leveraged in support of various political agendas. Terrorism or the threat of terrorism drives ratings, justifies discriminatory immigration policies, and allows politicians to score political points against opponents deemed “weak on terrorism.”

Terrorism experts (myself included) have opined on the need for a culture of resilience, one in which small terrorist attacks committed by lone assailants are treated as crimes and an unfortunate part of living in a free society, but not a cause for strategic shift or a massive investment of taxpayer dollars.  We should mourn the victims and learn lessons to prevent future attacks, but our political leaders need to put attacks in context as one of many risks that come with living in a free society. Yet, as appealing as such a response may be to terrorism experts, it’s unclear if such resilience is actually possible in the hyper-partisan and sensationalist media environment in which we live.

Every time there is a small terrorist attack, the media swarms to cover the story – both the attack itself, as well as all of the misses that allowed the attack to proceed. Politicians introduce new legislation, and pundits blast the administration for its mistakes. Even outside of the crisis period following an attack, politicians have found it difficult to speak rationally about the threats we face. Obama was pilloried for reportedly suggesting – behind closed doors – that Americans should put terrorism in context as a peril that is less dangerous than the risk of drowning in a bathtub.

I remain convinced that we must embrace resilience as a concept, but U.S. officials should be asking: What is actually possible and how hard are we willing to work to achieve resilience? Maybe it’s possible, maybe it will seem too hard for politicians and administration officials engaged on a range of strategic communications priorities. But if we are unable to mitigate media and political overreaction, we may well be doomed to a zero-risk posture where we send troops after every two-bit terrorist or talented propagandist driving his followers to violence.

Beyond these five questions, there are other strategic questions about the Forever War: What opportunity costs do we incur by investing in overseas wars rather than what we sorely need right now – things like domestic public health, infrastructure, and economic development? What costs do our overseas allies and local population bear for our counterterrorism campaign (particularly in light of new estimates that “37 million people have been displaced by America’s war on terror.”)? Where should terrorism rank on the list of national security priorities? Do we maintain any overseas counterterrorism presence once we have concluded the Forever War?

But in order to answer these questions, and find a path out of the Forever War, we must begin by examining the assumptions that have underpinned our fight all along.

Image: A U.S. Army helicopter flies outside of Camp Shorab on a flight to Camp Post on September 11, 2017 in Helmand Province, Afghanistan. Photo by Andrew Renneisen/Getty Images