Little about this attack is shocking. It is precisely what we all know and have come to expect from followers of ISIS and other radical Islamic ideologies. It is also precisely what a common-sense observer would expect to happen in a place like Germany given Angela Merkel's policy regarding national borders and the migrant crisis over the last two years, which led Germany to accept over a million people who just walked into the country mainly from the middle east, in most cases with no paperwork, vetting or any oversight whatsoever. 

The only "surprise" has been the specific time and location of the terrorist attack. The same will be true for the next one, and the next, and the next. Such is the horrific nature of terrorism.

Merkel failed the leadership test and has been failing consistently for years. The test is over, the consequences are hers to hold, and there are no retakes because innocent Germans are now in the ground. The chickens are coming home to roost now, that's all.