Islamist militias in Libya receive weapons and financing directly from foreign benefactors like Qatar; a Muslim Brotherhood figure, Abel al-Rajazk Abu Hajar, leads the Tripoli Municipal Governing Council, where Islamists are reportedly in the majority; in eastern Libya, there has been no resolution of the assassination in July of the leader of the rebel military, Gen. Abdul Fattah Younes, suspected by some to be the work of Islamists.

Mr. Belhaj has become so much an insider lately that he is seeking to unseat Mahmoud Jibril, the American-trained economist who is the nominal prime minister of the interim government, after Mr. Jibril obliquely criticized the Islamists…

Adel al-Hadi al-Mishrogi, a prominent businessman who began raising money for the anti-Qaddafi insurgents early in the revolution, is not convinced by the Islamists’ declarations of fealty to democratic principles. He pointed to a well-organized Islamist umbrella group, Etilaf, which he said had pushed aside more secular groupings.

“Most Libyans are not strongly Islamic, but the Islamists are strongly organized, and that’s the problem,” Mr. Mishrogi said. “Our meetings go on for hours without decisions. Their meetings are disciplined and right to the point. They’re not very popular, but they’re organized.”