Any loss of life in Europe by terror would be horrible. That having been said, if a major attack did take place, it would (or should?) put some spines into Europe's national leaders.
I spent some time last week with two college-age Swedish tourists. The fellow was concerned that an Iranian was "hassled" in Paris, before boarding a flight to the US. I calmly explained that MOST Americans aren't very much concerned. If terrorists hit Stockholm or Gothenburg, he would be less concerned, too.
I offered him some history: that the US doesn't start these things, thereby giving us moral high ground. I further taught him that only after 25 percent of Sweden's people opted to come to north America, did the government over there change to provide a place worth staying in.
English is mandatory for all students in Sweden, not Russian. That says something. (Europe haters: I love Europe and Europeans. I lived there. I DON'T like their governments).