It may seem unlikely, given their self-publicised appetite for slaughter and mayhem. But like any other high-profile cause, international jihadism is not immune to the charge that standards have slipped over the years.
A decade ago, when Osama bin Laden was in charge, he made it clear that even al-Qaeda had a code of conduct. In post-Saddam Iraq, hefretted over his affiliates' fondness for beheadings, fearing that spraying infidels' blood in such spectacular fashion might stain the organisation's good name. In chaotic Somalia, he once rejected an application from al-Shabaab, saying that what such a failed state needed first was international aid, not al-Qaeda.
How times have changed. Today, al-Qaeda's effective successor, Isil, takes in pretty much everyone and anyone. Gone is Bin Laden's jihadi gentleman's club that worried (sometimes) about whether it was right toslaughter Shias or aid workers, or to destroy ancient artifacts. In has come an outfit that prides itself on its brutality, and welcomes all and sundry into its ranks, including teen brides and ex-gangsters from the streets of London.
Hence it was no great surprise two days ago when Boko Haram, the Nigerian militant sect run by the semi-psychopathic Abubakr Shekau,declared that it was joining Isil. On Saturday, Shekau, who claims to enjoy killing people in the same way as he likes killing chickens,issued an audio statement swearing allegiance to Abubakr Al-Baghdadi, Isil's leader.
Bin Laden's al-Qaeda had rules... albeit loose ones
Whether Isil really needs Boko Haram is another matter, given that Shekau's main gig is kidnapping schoolgirls and terrorising villages in a very remote part of north-east Nigeria. But given how unfussy Isil seems about the company it keeps, most terror analysts believe Baghdadi will let them into the club anyway.
The real question, though, is what exactly Boko Haram will get back? And that is rather harder to answer. In theory, there are some fringe benefits to being an Isil affiliate. Rather like getting a Michelin Star, it helps put Boko Haram on the international jihadi map, making it easier to recruit. It may also mean help with media strategy and logistics, perhaps even weapons and fighters. After all, Isil now also have a foothold in Libya as well.
But closer examination suggests that this may fall short of helping Boko Haram become the West African arm of some global caliphate. Isil, for all the fear that it inspires, is not the UN or Nato. It controls a few patches of hotly-contested turf in Iraq and Syria, nothing more. Its affiliates cannot convene for annual strategy meetings, nor can they travel or communicate easily.
While a map showing Isil outposts in Nigeria, Libya, and perhaps one day also Somalia, might look frightening, it obscures the fact that between the three lies a vast tract of the Sahara desert, not to mention several hostile nation states.
Brothers in arms - Abubakr Shekau has pledged allegiance to Abubakr Al Baghdadi
Such fighters will not be able to move back and forth between these different outposts in the same way as Isil's men can between Raqqah in Syria and Mosul in Iraq. Instead, they may well up suffering the same problems as other big international organisations, where a touted international ideology founders under the weight of local priorities and national differences.
For example, Boko Haram, for all their talk of transnational jihad, is partly also a tribal insurgency based on the historic grievances of theKanuri ethnic clan. As such, much of their activity involves operations to grab villages in their operating turf around Nigeria's remote north-eastern Sahel region, rather than carrying out carbombings of Western targets in Lagos or Port Harcourt.
Onward to Nigeria? Isil fighters may have little in common with Boko Haram
Likewise, it remains to be seen how amenable Isis's mainly Arab leaders would be to treating sub-Saharan Africans as equal partners. The CIA takes the view that Isis is too "racist" to do so, pointing out that prejudiced attitudes towards blacks are still extremely common in the Arab world.
And while it's true that a number of black Africans have been seen in the ranks of Isil's "foreign legions", any organisation that has carried out Nazi-style pogroms of Shias, Christians and other non-believers clearly has only limited respect for notions of "inclusivity".
Blood brothers? A group of racially-mixed foreign fighters in Syria
That, though, is to overlook the one benefit which comes automatically with declaring allegiance to Isil - whether they are accepted or not. And that is to inspire fear. In Iraq more than a decade ago, I spent time with a US commander, Colonel Aubrey Garner in the so-called "Sunni Triangle" area, where the anti-US insurgency was just beginning.
In the area he patrolled south of Tikrit, graffiti proclaimed the rule of a local insurgent group called the 9-11 Brigade. They had very weapons or expertise, and probably nothing to do with al-Qaeda, but as Garner put it: "It's like kids forming a garage band. They just think: ‘What is the baddest thing we can call ourselves?"
That, in all likelihood, is part of Shekau's game plan - to bask in the infamy of a movement even more fearsome than his own, which in turn gets kudos from his professed loyalty. It's a mutually beneficial arrangement. And in a club where there are no longer any criteria about who joins, that is probably the only criteria that matters.