Nigeria's militant group Boko Haram has long been associated with the global wave of Islamic fundamentalism, but their recent attacks on civilians and the kidnapping of children may have gone too far for even other terrorist groups to abide. According to Adam Nossiter and David Kirkpatrick at New York Times, other Islamic jihadists around the world, including many closely affiliated with al-Qaeda, have soured on Boko Haram's tactics, believing they "taint the image of the Mujahedeen" and bring scorn down upon the whole movement.
Al-Qaeda solidified a relationship with Boko Haram after the Nigerian government staged a massive crackdown on the group in 2009. Evidence has since emerged of al-Qaeda camps taking in Boko Haram insurgents and possibly offering them training. In some ways, the relationship has been a fruitful means for the militant groups to ally against a common Western enemy. But ties between the two have also been fraught for ideological and tactical reasons, according to the Times:
Boko Haram is in many ways an awkward ally for any of [al Qaeda] Its violence is broader and more casual than Al Qaeda or other jihadist groups. Indeed, its reputation for the mass murder of innocent civilians is strikingly inconsistent with a current push by Al Qaeda’s leaders to avoid such deaths for fear of alienating potential supporters. That was the subject of the dispute that led to Al Qaeda’s recent break with its former affiliate, the Islamic State of Iraq and Syria.
Practically, Boko Haram's focus on local villagers (rather than international targets) and the adherence to a cult-like religious belief clashes with al-Qaeda's model. In recent years, Al-Qaeda's top leadership has placed an emphasis on limiting civilian deaths, in order to avoid alienating possible supporters, while the Nigerian group appears to have gone in the opposite direction. On a more visceral level, it seems the group's recent kidnapping of hundreds of schoolgirls, with threats to sell them into slavery, has alienated other Islamic militants, some of whom expressed disappointment in online forums. The Times reports that one such user wrote that, “Such news is spread to taint the image of the Mujahedeen,” and another appeared surprised that "There is news that they attacked a girls’ school!”