Peter Bergen

Sheikh Rahman's fatwa was the first time that anyone associated with al Qaeda had given religious sanction to attacks on American aviation, shipping and economic targets.

Security services, from Afghanistan to the United States, should be alert throughout the Ramadan period, but especially on the 27th day of the holy month.

ISIS' key social media-encrypted platform is Telegram, which is engineered by a Berlin-based tech company that can simply ignore the rulings of American federal judges as well as legislation passed by the U.S. Congress.

Bin Laden's death is just a punctuation point on a set of problems they've had for a long time. I think the prognosis for al-Qaida and groups like it is really bad, and that's a good thing.

It is hard to imagine two more final endings to the 'war on terror' than the popular revolts against the authoritarian regimes in the Middle East and the death of bin Laden.

If the Arab Spring was a large nail in the coffin of al-Qaeda's ideology, the death of bin Laden was an equally large nail in the coffin of al-Qaeda the organization.

In Syria, a no-fly zone targeted at Assad's air force and safe zones for refugees fleeing the fighting would help tamp down the death toll that plays into the hands of ISIS and other Sunni militants who can position themselves as the only groups that are really defending the Sunni population.

Apostasy is a grave crime in Islam and punishable by death in the eyes of members of al Qaeda.

The reason that Islamist militants can assert that jihad is necessary against the perceived enemies of Islam is that there is sufficient ammunition in the Quran to buttress their beliefs. The same could also, of course, be said for the Old Testament, which is full of scenes of violent death visited on the enemies of God.

Syrian refugees fleeing to Europe do not go through anything like the rigorous process experienced by those who are coming to the States, and the volume of Syrians fleeing to Europe is orders of magnitude larger than it is to the United States.

Donald Trump's own mother Mary escaped the bone-crushing poverty of Scotland's remote Outer Hebrides for the promise of New York in 1929.

The special reverence that al Qaeda had for Sheikh Rahman was underlined by a two-hour propaganda videotape that the group's media division released in the spring of 2001, when the 9/11 attacks were in their final planning phase.