John Norris and Bronwyn Bruton write: On the morning of Oct. 4, a truck bomb exploded on a well-trafficked street outside the Ministry of Education in the Somali capital of Mogadishu, killing upwards of 80 bystanders, many of them university students. The attack brought an end to the relative lull that had held in Mogadishu since August, when fighters for the al-Shabab guerrilla forces withdrew from the city, and offered a stark reminder that the world’s most notorious failed state remains just that.

Somalia’s ruin can’t simply be chalked up as a case of Western neglect. For decades, the United States and international organizations have poured money into Somalia despite its relative geopolitical insignificance — first as a Cold War bulwark, then as a humanitarian emergency, and now as an effort to contain crime and terrorism. Just how much has Somalia cost us? To figure out the true financial burden that Somalia’s conflict has imposed on the world since 1991, we used a variety of official and unofficial sources, combined with some educated guesswork, and came up with an estimate of $55 billion. That figure includes everything from aid supplied by the Red Cross and defaulted World Bank loans to naval patrols off Somalia’s piracy-plagued coast and CIA-run detention facilities within the country.

$55 billion may be modest in comparison with the cost of the interventions in Iraq and Afghanistan — which together are likely to end up costing the United States more than $1 trillion, according to the Congressional Budget Office — but what’s remarkable is how little we have to show for it. For all the treasure expended there, Somalia is no closer to stability than it has been at earlier points in its two-plus decades of chaos. The country is currently experiencing the worst famine the world has seen in two decades, with more than three-quarters of a million people at grave risk of starvation, and remains riven by civil conflict, piracy, and extremism.

The world’s approach to Somalia has long been trapped in an unhappy middle: It has been insufficiently robust and well-designed to resolve the country’s conflicts but far too heavy-handed and frequent to allow the country to resolve its own problems. An entire generation of Somalis now views the “state,” whether it is the Transitional Federal Government or al-Shabab, as a largely predatory institution to be feared, not as a source of stability. Perhaps more than anything, the spending on Somalia demonstrates how the world — and Washington in particular — keeps groping for quick tactical fixes while failing to embrace the sensible diplomacy and the kinds of patient engagement that might help Somalia achieve peace.