When does speech become violence???

This editorial in the Washington Post highlights an issues that I believe is a critically important issue, have passionate feelings about, but am also conflicted.  Free Speech.

The article has two primary subjects.  One is the difference between European and US ideas about when racist speech is free and when it is not.  The Europeans are much more likely to make speech a criminal offense when it involves demographic-based hate - justifying this by calling it an incitement to violence (i.e. not just speech).  In the US, we require a lot more evidence of incitement.   We value the basic freedom of speech, no matter how ugly and hateful.  I am proud of this and cringe when I see how often groups jump to criminalize speech that they don't like. 

The other subject is the challenge that international access to user-generated content creates for creating practical and enforceable laws that match these different views (and others) on issues like speech.  If someone in the US writes a tweet/blog/etc that is legal on the US criteria but not in Europe, what happens when someone in Europe reads it and files a grievance?  Or if someone in Europe posts one on a US service?  The hateful speech is stored on a US server, but during the access copies are made on servers in both continents. Does this count?  Do we need some kind of internationally consistent regulation?  I would hate for us to give up our stronger protections.  Do we have some kind of international treaty where we decide together that it is where the author is located that matters? 

When international differences are economic, it's easy to resolve them by splitting the difference.  But when it involves a fundamental value, compromise is harder to do.  It feels wrong, the compromise might still violate your values, and no one is happy.