Dr. Ephraim Herrera, an expert on Islam and the Middle East, spoke with Arutz Sheva about the deadly terrorist attack in Manhattan last week.

"This attack in Manhattan was predictable, and it was almost certain that it would happen, because it is the fruit of a calculated strategy of the ideologue of Islamic State, Abu Musab al-Zarqawi, who invented the concept of the lone wolf attacker. You don't need to be affiliated with the Islamic State. Just read the instructions on the net, and carry them out. And that's what this jihadist did," he said.

He said that a similar terrorist attack "will almost certainly happen again."

Dr. Herrera said that US President Donald Trump must act to "Stem the tide of jihad. He has to put pressure on the Arab states and the Muslim states in order to stop this teaching of jihad, and also in the United States."