Religously motivated?

Bookworm calls attention to a piece in the Washington Post:

 

The Washington Post has a piece that ostensibly educates WaPo readers about the true nature of today's terrorists.  Interestingly (or do I mean typically) it tries to erase Islam from the equation:

3. Al-Qaeda is made up of religious zealots.

To the contrary, rank-and-file terrorists who claim to be motivated by religious ideology often turn out to be ignorant about Islam. The Saudi Interior Ministry has questioned thousands of terrorists in custody about why they turned to violence, and found that the majority did not have much formal religious instruction and had only a limited understanding of Islam. According to Saudi officials, one-quarter of the participants in a rehabilitation program for former jihadis had criminal histories, often for drug-related offenses, whereas only 5 percent had been prayer leaders or had other formal religious roles.

Maybe I'm reading the above text wrong, but it seems to say that, if you're not deeply familiar with Islamic doctrine, at a scholarly level, then you're not religiously motivated.  And if you're not religiously motivated, of course, than you're not really an Islamic terrorist.  Instead, you're just one more piece of the "man-caused disasters" currently plaguing the West.

As far as I'm concerned, if you use Islam, no matter how limited your understanding, as the justification for slaughtering civilians all over the world, than you are by definition an Islamic terrorist.