In his essay (and two recent books) Paul Collier lays out a detailed vision for how foreign aid and intervention might promote economic progress in the world’s poorest regions, areas populated by what he has called the “bottom billion.” The key problem, as Collier describes it here, is that:

A group of about 60 small, impoverished, post-colonial countries . . . . are structurally unable to provide the public goods . . . that are critical for decent quality of life and imperative for economic development. They have diverged from the rest of mankind.

This diagnosis leads him to the following prescription:

If countries of the bottom billion are structurally unable to supply security and accountability, then some form of international supply is required.

For reasons I will discuss later, international provision of national public goods may be neither desirable nor even possible. But first things first. Collier’s argument rests on the claim that dozens of the world’s poorest countries, mainly in Africa, “have diverged from the rest of mankind” and are “structurally unable” to develop economically. This is a claim worth considering carefully. Are the world’s poorest, and overwhelmingly African, countries a lost cause?

In my view, this central premise is greatly overstated. Collier ignores the economic record of the past decade. In a Boston Review forum on African economic development last year (since published in book form as Africa’s Turn?), I argued that the period since around 2000 has seen sub-Saharan Africa sustain its best economic growth performance since the early 1970s. Over the past decade, continent-wide per capita income growth was 3 percent per-year, hardly equal to the breakneck pace of China or India, but a huge turnaround for a continent that suffered large drops in living standards from 1975 to 2000.

Multiple factors appear to have played a role in this nascent African recovery, including high commodity export prices; growing foreign investment from new partners, including China; new technologies, such as cell phones, that have improved market efficiency, financial access, and community organizing; and better economic policymaking. Growing competition among political parties and the expansion of democracy may also have played a role in promoting greater accountability and better policies, although it it is difficult to do more than speculate about the roles of these political factors.

Africa is still lagging behind the most successful Asian countries, and many of its gains are fragile. Still, I disagree with Collier: the past decade surely offers hope.

Putting this disagreement aside, it is still worth considering what Collier’s policy proposals would look like in practice. A sharp increase in foreign military intervention is a central element of Collier’s plan. Outside forces would be empowered to invade countries suffering from civil war, or where rulers are unwilling to hold fair democratic elections, in order to impose security and accountability.

It is not clear that this sort of plan is desirable even if it is feasible. Which authority can impartially decide which elections are sufficiently fair to avoid foreign military intervention? Does a civil conflict that displaces ten thousand civilians merit a UN peacekeeping response, or is one hundred thousand the magic number? Most importantly, given limited budgets and military capacity, how can we be sure that these choices will not simply be dictated by the geopolitical interests of the great powers, rather than by objective criteria? Other academics, most notably William Easterly in his New York Review of Books discussion of The Bottom Billion, have leveled similar critiques against Collier’s proposal.

The case of the Rwandan genocide is particularly instructive. Collier claims that the world’s response in Rwanda was characterized by “passivity,” but the opposite is more accurate. There was a large UN peacekeeping force on the ground, and France sent combat troops to step in. The problem was not a lack of intervention but rather the political constraints that made the “right” intervention impossible. With its failed military effort in Somalia still fresh in mind, and mid-term Congressional elections just months away, the United States was unwilling to authorize UN Security Council plans to bolster the peacekeeping force. And rather than fighting to protect civilian victims of the slaughter, France chose to back the government carrying out the genocide, its long-standing ally. The same sorts of real-world political considerations could doom the future military interventions Collier advocates.

As for feasibility, Collier focuses on Britain’s successful and relatively cheap military intervention in Sierra Leone, which rapidly ended a brutal civil war there, and where foreign troops have buttressed political stability for nearly a decade now. But that is only one instance. We do not yet have sufficient evidence to predict when such interventions will succeed and when they will fail—as in Somalia and, most famously, Iraq, the latter a country where foreign intervention arguably increased political instability and violence. Bringing both successes and failures into the equation makes the cost-benefit analysis much murkier. Collier acknowledges the weakness of the existing research on peacekeeping effectiveness but seems to brush it aside. I think this is a mistake.

In addition to military success, Collier’s proposal requires foreign actors to support major shifts in governance, but the resources and political will to restore democracy in the poorest corners of the globe may be in short supply in a period of worldwide economic recession. This ties into a much broader point about an outsider or group of outsiders’ ability to transform other societies. Even the infinitely wealthy, militarily powerful, and altruistic world community Collier imagines may be unable to bring fundamental institutional change to other societies. Students of economic and political development still know precious little about how to set in motion the social transformations necessary to achieve durable democratic norms, popular accountability, and peaceful coexistence across ethnic divides. Even if outside military powers are successful at ending civil wars, they will find themselves at a loss in setting up stable democracies. How far should they go in this mission? And how will the world’s poorest countries ever attain the experience, insight, and institutions necessary for economic development if wealthy countries—however well-intentioned—are always prepared to take responsibility for the fate of the poor?