This is the third category of Muslims that lurks between “moderates” and “radicals”: “sleepers,” Muslims who appear “moderate” but who are merely waiting for circumstances to turn to Islam’s advantage before they join the jihad; Muslims who are waiting for the rewards of jihad to become greater than the risks.
There is no lack of examples of these types of Muslims. The following are testimonials from non-Muslims, mostly Christian refuges from those regions of Iraq and Syria now under Islamic State (or other jihadi) control. Consider what they say about their longtime Sunni neighbors who appeared “moderate” — or at least nonviolent — but who, once the jihad came to town, exposed their true colors...
...Those are the opening paragraphs of an important new article by Raymond Ibrahim. He then quotes non-Muslim testimonials from refugees. Check it out: When Muslims Betray Non-Muslim Friends and Neighbors.
This phenomenon is in line with Islam's Rule of Numbers, which Ibrahim has discussed elsewhere. The larger the percentage of Muslims in an area, the more aggressively they insist on Islamic norms.