A report on the Muslim Brotherhood in Syria, by Aron Lund, makes these findings:

The Syrian Brotherhood is not as strong as commonly believed. The incessant focus on the Brotherhood by the Assad regime, Western nations, and rival opposition groups has helped it build a fearsome reputation. Its actual political and organizational capability appears to be far more modest.

The failures of others have benefited the Brotherhood. The real reason for the group’s success in the exile community is the extreme disorganization of the rest of the opposition. As long as rival actors cannot get their act together, the Brotherhood will win by default.

The Brotherhood tries to distance itself from extremism. Despite its theocratic ambitions and a past history of sectarian violence, the Brotherhood now promotes a moderate Islamist approach and seeks to accommodate concerns about its ideology. Since 2011, it has consistently cooperated with secular groups, spoken in favor of multiparty democracy, and worked through mainstream opposition frameworks such as the Syrian National Council, the National Coalition of Syrian Revolutionary and Opposition Forces, and the Free Syrian Army.

Several armed groups linked to the Brotherhood fight in Syria. The leadership refuses to admit to having an armed branch, but Brotherhood exiles have been funding armed groups since late 2011. The organization now controls or sponsors dozens of small paramilitary units inside Syria.