When President Trump offhandedly tossed out a comment about crime in Sweden as a result of an over-accepting immigrant policy, many gleefully seized the opportunity to ridicule his remarks and dismiss the concerns of those reluctant to open the gates to refugees from the Middle East. Trump’s oppenents were quick to point out that Sweden has far less murders than the US, and argued that the influx of refugees has been a completely positive boon to the country.

Alas, it seems they spoke a tad too soon. Two days after Trump’s remarks, an attempt by Swedish police to make a drug arrest in the predominantly immigrant neighborhood of Rinkeby, Stockholm resulted in riots, looting, and violence. Angry crowds threw stones, torched cars, and looted stores. Several people were injured in the violence. As a matter of fact, it’s not the first time Rinkeby has erupted in riots, either; the neighborhood featured two days of violence against police in 2010, and again in 2013, this time for almost a week.

Now, to be fair, this does not necessarily show that President Trump’s reluctance to open the gates to refugees from war-torn countries like Somalia or Syria is right. What it does demonstrate, however, is that the concerns and fears about allowing in mass numbers of refugees are not baseless. Many proponents of refugee settlement in the US are all-too-quick to arrogantly assume that the only possible motivation of their opponents is bigotry and uneducated anti-Muslim sentiment. All of Trump’s supporters, they condescendingly assume, are Islamophobic simpletons. The truth, though, is that not all cultures are created equal. The reality is that, while not all versions of Islam are incompatible with Western values of tolerance and liberty, radical Islam most certainly is. And, while liberals tend to downplay the role of ideology in violence and war, preferring to focus on economic status, radical Islam does have an appeal among a sizeable portion of the Middle East, a portion large enough to justify concerns that unquestioning hospitality may not be the wisest move right now.