National football fans are not like club football fans. There is very little hooliganism in international football, nor would anyone have any energy for it in the searing heat.
I took a train from Nice to Paris right after this happened and two English "fans" shared the compartment I was sitting in. It was one of the most frightening experiences I've ever had traveling. All they could talk about was recounting their "exploits" in the events described in your linked article. One even bragged that he "got a Tunisian so good he might not pull through."
The lack of humanity they displayed was an eye opener for me and helped me come to the realization that Soccer/Football has become the proxy for war in Europe. While that is, all things considered, an excellent development (I'll take hooliganism over world wars), it's also scary that people seem to have a deep-seeded, tribal need to fight and, when we do, we seem to lose all compassion for the opposition. Events like the World Cup seem to play on this need rather than trying to quash it.
Violence and the Euro 2004, in Portuguese.
http://ielt.fcsh.unl.pt/ielt/pt/acontecendo/no-passado/132