As a pure war on terror matter, we should probably welcome Europe's decision to roll out the welcome mat for lots of Moslem migrants who will allow ISIL to infiltrate terrorists into Europe and who will provide a recruiting and support pool from the sympathetic portion.
After all, we've long said that we fight the jihadis "over there" in CENTCOM so we don't have to fight them "over here" at home.
Europeans have been mostly unwilling to help us fight the jihadis over there. So now the Europeans will finally become fully belligerent partners in the war on terror by fighting a good chunk of the jihadis in their own "over here" location.
As a humorous aside, note in that linked article that Merkel issued her welcome to migrants convinced that few would react to that incentive. It was going to be all good publicity for no real sacrifice. She changed her mind when the flood became too big to ignore. But it's too late.
Welcome to the war on terror. Good luck on the European Front. Our people can't be on all of your trains, you know.
But perhaps we can send James Taylor again.