When I'm scratching my head, I often look at the misunderstood-item with this question: what is the gain and for whom? I can't apply that question here, because I don't even grok the skeleton of the thing: are they intimating they don't want Americans to travel? And if so, what is the gain?
It seems that if fear-mongering is the goal, then they would be "intimating" that "Americans" are not safe in their own home. That would be far scarier than this bizarre sniping at which they're hinting..
If they've received intelligence that tourist-sites in Europe are the object of some scheme, well surely more than "Americans" are at risk, and such warnings should be international, not just national.. In other words, "Americans" are not the only tourists in "Europe".
Unless... that's precisely what has happened, that they've gotten word that some events are about to take place, and this lame article is the best they can do in putting out a warning.
It's all very confusing.
Al Qaida - a (I) Am. construction.
I'd consider the possibility that this is just a way of keeping all that going - which puts it into fear-mongering. But the rest of it still doesn't make sense. "Europe" is a big place, eh?