In The Sun Also Rises, Ernest Hemingway famously distinguished two ways to go bankrupt—"gradually, then suddenly." The same is sometimes true of wars. In World War II, years of exhaustion and attritional campaigns were followed by the rapid collapse of Germany and Japan in its the final phases. In 1975, the Republic of Vietnam failed to stop the Democratic Republic of Vietnam's onslaught and was eliminated in a matter of weeks. Television cameras captured the iconic images of this defeat as masses of Vietnamese people tried to enter the US embassy and evacuate the country. In the 21st century, the sudden fall of the Islamic Republic of Afghanistan in the face of Taliban attacks in 2021 sharply contrasted with the long-term mission that NATO forces conducted in Afghanistan since 9/11.

The end of a war colors the interpretation of the entire conflict. Interim victories are typically seen as false hopes when weighed against the final verdict of a lost war. However, in their new book, The Ledger, historians David Kilcullen and Greg Mills oppose interpreting NATO success in Afghanistan as ephemeral. They believe there were real chances for NATO forces and sponsoring governments to change the outcome in Afghanistan, even in 2021. The main reason for the failure of NATO to succeed in Afghanistan was the inability of NATO governments, and Western governments more generally, to understand that their assumptions about Afghanistan were unrealistic.

Believing the mission in Afghanistan was winnable, the authors substitute the mission that the George W. Bush administration and subsequent administrations set out for one that was smaller in scale and departed from public pronouncements of NATO and US leaders. They argue that the Bush administration did not intend to conduct nation building in Afghanistan. However, Brendan Gallagher has convincingly argued that President Bush in fact espoused a policy of building a democratic Afghanistan.[1] But his cabinet, specifically the Secretary of Defense Donald Rumsfeld, refused to support this policy.

Kilcullen and Mills contend that the international community did not need to create a democratic Afghanistan to be successful. But the Bush administration (and subsequent US administrations) nonetheless hewed to this as the definition of success for the NATO mission in Afghanistan. The authors never precisely distinguish between these two objectives.

The authors list factors that contributed to the failure in Afghanistan. The most important were (a) the lack of a single unified campaign plan, (b) the fact that geography overrode the international efforts in Afghanistan, (c) the poverty of local ownership, and (d) the failure of the international community to discriminate between the reality of Afghanistan and what policy makers wanted to be true in Afghanistan. Three of these factors were the direct result of decisions by policy makers and senior military leaders; the geographic factor was ignored by senior leaders.

The lack of a single campaign plan, the authors argue, meant that NATO efforts lacked synergy or cohesion. NATO member states concentrated on local, not theater-level operations. And commanders strove to make quick advances in their specific areas while they were still in command. This meant that resources often went to problematic areas where leaders could show more dramatic advances instead being used to reinforce successes in areas with fewer problems.

The poverty of local land owners and the inability of international actors to truly understand Afghanistan exacerbated the lack of a campaign plan. Commanders and international leaders did not want to risk their success by allowing Afghans to fail. Instead, they did not allow Afghans to take credit for the success of Afghanistan. Hence the lack of governmental structures able to withstand the stress of independent nationhood.

The authors also draw attention to the problems of flawed assumptions. International leaders could not square what they wished to be true of Afghanistan with what was actually true. This is a common issue in military conflict; the authors have avoided this blunder by properly researching the context of a given region or conflict. NATO policy makers and senior leaders simply assumed the Western model of government and society were attractive and easily adopted. They did not understand the Taliban network and so failed to counter it. Nor did they seek to remove the Taliban haven in Pakistan.

The geographic aspect of conflict also showed the problem of flawed assumptions. Geography matters, even in the 21st century. The authors argue convincingly that the ability of Taliban insurgents to find refuge in Pakistan prevented the NATO coalition from eradicating it completely. NATO leaders never effectively countered or changed Pakistan's unwillingness to help in Afghanistan. Pakistani leaders saw the Soviet withdrawal and the resulting Afghan civil war as a betrayal by the United States. When the US-led coalition needed Pakistan's assistance, its leaders were unwilling to help because they saw the result of their previous efforts with the Soviets.

These two issues—the need for a quick victory and an effective government in Afghanistan—had implications the authors explore in some detail. They specify what leaders and commanders should do differently in the future, but they overlook the Bush administration's goal of building a democracy in Afghanistan. While the authors claim this need not have been the main objective of the conflict, it was the benchmark for the formative part of the conflict. Also, subsequent US administrations faced the war in Afghanistan under the influence of the Bush administration's failure to create a viable democratic Afghanistan.

The authors do not investigate the Bush administration's failure to help build a functioning democracy in Afghanistan. In fact, they assume it never considered nation-building to be important. This is the biggest shortcoming of The Ledger in that it undercuts the fundamental premise of the work—that the conflict in Afghanistan was winnable given a more coherent campaign centered on integrating the Taliban into a post-conflict Afghan government.

The Ledger offers valuable insights into the problems NATO had in Afghanistan. Scholars and policy-makers will benefit from its authors' acute inquiry into the sources of those problems.