Mr. Nkurunziza first came to power in 2005, when he was elected by Parliament. Because he was not elected by “universal direct suffrage,” as mandated by Article 96 of the Constitution, the president claims that only his second term is covered by the article’s term limit clause. But opponents argue that according to Article 7, the people’s will is sovereign, whether it is indicated by direct elections or mediated by their representatives in Parliament; in other words, they maintain that Mr. Nkurunziza’s election in 2005 counted as his first term.

Maj. Gen. Godefroid Niyombare’s decision to try to depose Mr. Nkurunziza is evidence that the political and military elites are themselves deeply divided over the issue. (According to a Reuters report, the general is now under arrest.) Both sides of this conflict have the capacity to mobilize loyalists and wreak violence.

Burundi’s army is especially volatile, comprising an amalgamation of militias organized around ethnic quotas. The president’s party, the National Council for the Defense of Democracy, also counts among its membership hard-liners with the potential to inflict violence on opponents.

An escalation of the crisis in Burundi is still preventable. But the longer the conflict continues, the harder it will be for the international community to come up with a viable solution.

The United States has been focused on the Burundi problem for several months. The former Wisconsin senator Russ Feingold, who was until February the United States special envoy for the Great Lakes region of Africa, warned of impending problems should Mr. Nkurunziza attempt to run for a third term. In April, the assistant secretary of state for democracy, human rights and labor, Tom Malinowski, traveled to Burundi to persuade Mr. Nkurunziza not to risk a new round of conflict. The presence in the region last week of the State Department’s most senior Africa expert, Assistant Secretary Linda Thomas-Greenfield, also reflects Washington’s concern to head off trouble in Burundi.