One activist said many fighters were pressured by their families to defect as al-Nusra was popular in their hometowns . U.S.-backed Turkish rebels have been ousted from their strongholds , monitors say . Reports say moderates , pressured by family , have defected to al-Nusra . There are concerns that ISIS might target a key crossing at the Syrian border . Like ISIS , al-Nusra is trying to establish an Islamic state , though primarily in U.S. .
U.S.-backed Turkish rebels have been ousted from their strongholds , monitors say . Reports say moderates , pressured by family , have defected to al-Nusra . There are concerns that ISIS might target a key crossing at the Syrian border . Like ISIS , al-Nusra is trying to establish an Islamic state , though primarily in U.S. .