If you haven't read it already, I highly recommend bookmarking The Counterterrorism Blog.

Buttressed by some highly respected terrorism experts, this site offers credible insight and analysis, rather than just punditry and blog-pinion.

A post from yesterday talks about why we should indeed worry about the non-assimilation of Europe's exploding Muslim population. While Europe naively is happy to offer the benefits of citizenship to its immigrants, while not asking for some assimilation in return, they allow a growing segment of their population to essentially have their own cross-border society, Eurabia.

The problem we face is that those among the 15-20 million Muslims in Europe, are hidden many Jihadists who would do us harm.

While the vast majority of Europe’s Muslims are peaceful, law-abiding people, that large population provides a fertile recruiting ground and easy operational cover for a dangerous and growing cadre of radical jihadists. Those jihadists, some of whom are recent newcomers from Arab and other predominantly Islamic countries, are increasingly “home-grown” Europeans.

This of course is not a surprise, but the rub is that these jihadists are most-times 'clean' European citizens, who can easily enter our country.

...there is now a significant cadre of radical Islamic jihadists who hold European citizenship, those people are also eligible to enter the US under the Visa Waiver Program …without any pre-screening by a US Consular officer overseas. If such a person has not surfaced on any Intelligence Agency or Law Enforcement radar screen and is not in a lookout system “watch list,” they would likely be admitted into the United States....The “clean” Euro-jihadists need only board a US-bound airliner and walk up to a border inspector to be admitted under the Visa Waiver Program....

So we cannot simply dismiss incidents like this as "Europe's problem", because Europe's naivete and our lax borders have made it our problem.