A few months ago, I sat at a friend’s kitchen counter drinking whiskey and sharing deployment stories. He asked me if there was one I’d never told anyone. I realized it had been a year since the Niger mission that left four American service members dead and sparked questions about the United States’ role in the region. So I told him about Oaken Sonnet, a similarly botched mission that took place in 2013, and about why it still haunts me.

The week before Christmas in 2013, I was one of two intelligence officers who took the initial report of an attack on American forces in South Sudan that the American public has not heard enough about. If it had — and if the American military had studied the mistakes made in the mission’s planning and learned from them — the loss of those four soldiers in Niger in 2017 might have been avoided.

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I was part of a Special Operations detachment stationed in the Arabian Peninsula. A few of my teammates were on loan to a Special Operations unit based at Camp Lemonnier, a large military installation in Djibouti. They had been assigned to evacuate American citizens from a United Nations compound in Bor, South Sudan, the center of violence in a civil war that had broken out days before. Because my teammates fell under the operational control of United States Africa Command, our own commanding officer had no say in their employment, and our unit could not be involved in mission planning, including intelligence support. Their mission, which was ultimately overseen from Stuttgart, Germany, was briefed by intelligence teams based in Djibouti and Stuttgart as being in a “permissive environment,” meaning it was supposed to be low-risk.