Seizing the opportunity to gain new audiences and enhance support, terrorists and extremist groups have developed a nuanced and targeted approach to recruiting women.
For example, as part of a social media campaign to extol to women the virtues of jihad in Iraq and Syria, Umm Layth - thought to be a British woman in Syria married to a fighter - tweeted: "The wives of the Shaheed ('martyrs') are the strongest types of women I have come across. Epitome of independent women." To oppose this trend, government and international efforts to counter violent extremism (CVE) need to more proactively engage with women and integrate a gender dimension into CVE policies and programmes.
The presence of women in fighting corps should come as little surprise. Female fighting cadres from the Liberation Tigers of Tamil Eelam were reputed to be even more ferocious in many instances than their male counterparts, and women figured prominently in leftist militant groups like Colombia's FARC rebels and the Red Army Faction in Germany, as well as groups like the Chechen "Black Widows".
Yet, women have often come as an afterthought in official efforts to prevent and counter terrorism and violent extremism.
Terrorist groups have unfortunately been ahead of governments, which are often more constrained by protocol and bureaucratic silos, in engaging with target audiences. Al- Qaeda's Inspire magazine dedicated segments specifically to women, and the Islamic State (ISIS) has developed a media strategy that includes Twitter campaigns such as that by Umm Layth.
It is not immediately clear how many of these campaigns are driven by ISIS itself and how many are independent feeds, but the medium allows them to appear to address any potential recruits directly and discuss issues ranging from the mundane to the profound.
For example, one woman has recently tweeted her desire to be the first British woman to kill a US or UK citizen. Others tweet about the joys of living in the "Islamic State" and the camaraderie among women who await news of their husbands' or sons' "martyrdom".
Reports of an all-female ISIS brigade enforcing draconian interpretations of syariah law on women have shocked audiences more accustomed to seeing the all-male Taleban or Al-Qaeda cadres subjugating women in their homes and communities.
This is not to indicate some kind of feminist revolution among Islamist extremists. Many women continue to play traditional roles supporting the men involved in combat operations. Messages like Umm Layth's even strenuously warned that female jihadis should expect to be involved in the domestic sphere in Syria, flatly announcing that it is "completely impossible" for women "to participate in battle", despite important historical precedents in Islam for women's participation in war.
The importance of this debate lies in understanding why women choose to become fighters or suicide bombers.
For some, it represents a proactive choice, an opportunity to challenge societal norms and assert equality in a way that is not available to women outside combat roles. For others, the reasons for joining extremist groups may lie in histories of sexual abuse or coercion by family members as a means of saving face, restoring familial honour or avenging the death of loved ones.
Understanding why women choose to join extremist groups, and what makes them appealing, is critical to developing more nuanced and targeted efforts to counter violent extremism or prevent terrorism. Further research about the impact of violent extremism on women, and their roles in both supporting and preventing it, is sorely needed.
The sophistication of the media strategies developed by Al-Qaeda and its derivative groups, including AQAP (Al- Qaeda in the Arabian Peninsula) and ISIS, also challenges governments and international organisations which are often more constrained in the manner and content of media messaging.
While robust measures may be needed to address immediate security concerns, a more strategic approach to counter violent extremism requires a better understanding of how the underlying grievances affect young people men and women - who are often the most vulnerable to recruitment by extremists.
Analyses of risks and threats need to integrate a gender dimension; counter-narratives need to be carefully tailored to ensure they reach female audiences; governments, institutions and civil society need to more proactively include women both as participants and beneficiaries in order to address these challenges.
The writer is Head of Research and Analysis at the Global Center on Cooperative Security. The Global Center works closely with governments, civil society and international organisations to develop cooperative responses to security challenges.