GOVERNMENTS and newspapers around the world attributed the horrific Christmas Day bombings of churches in Nigeria to “Boko Haram” — a shadowy group that is routinely described as an extremist Islamist organization based in the northeast corner of Nigeria. Indeed, since the May inauguration of President Goodluck Jonathan, a Christian from the Niger Delta in the country’s south, Boko Haram has been blamed for virtually every outbreak of violence in Nigeria.

But the news media and American policy makers are chasing an elusive and ill-defined threat; there is no proof that a well-organized, ideologically coherent terrorist group called Boko Haram even exists today. Evidence suggests instead that, while the original core of the group remains active, criminal gangs have adopted the name Boko Haram to claim responsibility for attacks when it suits them.

The United States must not be drawn into a Nigerian “war on terror” — rhetorical or real — that would make us appear biased toward a Christian president. Getting involved in an escalating sectarian conflict that threatens the country’s unity could turn Nigerian Muslims against America without addressing any of the underlying problems that are fueling instability and sectarian strife in Nigeria.

Since August, when Gen. Carter F. Ham, the commander of the United States Africa Command, warned that Boko Haram had links to Al Qaeda affiliates, the perceived threat has grown. Shortly after General Ham’s warning, the United Nations’ headquarters in Abuja was bombed, and simplistic explanations blaming Boko Haram for Nigeria’s mounting security crisis became routine. Someone who claims to be a spokesman for Boko Haram — with a name no one recognizes and whom no one has been able to identify or meet with — has issued threats and statements claiming responsibility for attacks. Remarkably, the Nigerian government and the international news media have simply accepted what he says.