Yemenis say he is little known in his home country, because he grew up in America, and preaches in English. But on the Internet, he is the jihadist equivalent of a pop-star. His audio lectures have gone viral, as he tries to radicalize young Westerners by tugging at their heartstrings.

"Palestinian children, charging at the soldiers full speed, armed with nothing but rocks and wearing nothing but trousers and T-shirts are cowards? I fail to understand that," he added.

This comes at a time when authorities are worried by an increasing number of Westerners arrested in connection with al-Qaida, including a Pennsylvania woman arrested last week known as "Jihad Jane." In the past two years, more than a dozen Americans have been arrested for or identified as supporters of violent anti-Western jihad.

And after months of near-silence, Anwar al-Awlaki is once again is trying to inspire this trend, or at least re-claim his reputation as "the Osama bin Laden of the Internet."