Germany axe attack has the usual features

Even the pro unlimited immigration BBC have to report that the latest terrorist attack has the usual features. 

It was carried out by a young Muslim, this time a recent immigrant, who allegedly shouted "Allahu Akbar" (Our God is greater) as he carried out the attack. 

At what point will Angela Merkel and the rest of the western liberal elite realise the enormity of their mistake in massively increasing immigration from various Islamic war zones into Europe? How many innocent Europeans will die before and after they do?