The perp had an active jihadistic web presence, but only in the last few months. The Germans are calling this phenomenon "instant jihadism".
German authorities view the phenomenon as quite dangerous. Usually, in monitoring group behavior, authorities can follow up on clues left by the groups activities.
In this case, the perp was motivated to act by a video he had watched the night before about the raping of muslim females. The video was sent to him by a facebook friend.
The perp had led a very unsuspicious life and had in no way appeared on any terror investigator radar screen. Only after the fact could they reverse engineer his increasing jihadistic tendancies over the last few months via his web presence.
The title of the article refers to the nightmare that lone "instant jihadists" presents for the German authorities. There is virtually no way to track them before an attack occurs.
This was the first jihadist attack resulting in deaths for US personnel in Germany. It had been a jihadic goal for quite a while.
This should be a warning for the US. As Col Allen West says, "we must recognize our enemy". It is alarming to me to see that the US MSM isn't devoting much coverage to the attack, especially to the details described above.
THhank you Longjack for the additional article and your input.