Asked why the United States is not acting now, she gave an answer that, again, we found surprising. “It’s not that simple,” she said. “The international community isn’t unified, there’s no agreement to intervene, there’s no basis in international law to intervene.”

Regarding “Not simple,” we all can agree. The longer the conflict has dragged on, the more Islamist radicals have come to the fore, muddying the question of whom the United States could support.

But what of humanitarian intervention of the sort Ms. Rice favored when people were starving in Darfur? In that case, she seemed to have a different view on international law. “Others will insist that, without the consent of the United Nations or a relevant regional body, we would be breaking international law,” she wrote with two co-authors on the opposite page in 2006. “Perhaps, but the [U.N.] Security Council recently codified a new international norm prescribing ‘the responsibility to protect.’ It commits U.N. members to decisive action, including enforcement, when peaceful measures fail to halt genocide or crimes against humanity.”