KAIROUAN, Tunisia — The third annual meeting of Ansar Al-Sharia (Supporters of sharia or Islamic law) was supposed to be a huge gathering — organizers had said 40,000 would turn out to support the installation of an Islamic state in Tunisia. With authorities having banned the congress, many feared confrontation, even bloodshed.

Instead, the square in front of the Great Mosque of Kairouan was filled with police running training drills, and the violence — a young man killed in a poor suburb of Tunis — took place 150 km [93 miles] away.

So what happened? Slah Ahmidi, a resident of Kairouan who works at the local tobacco factory, summed up the opinion of most observers: “The leaders [of Ansar Al-Sharia] made a mistake. They wanted to challenge the state and the state said, 'No one challenges the state, the law applies to everyone.'”

The show of force by Tunisia's security institution was clear and effective. In Kairouan, the show was exactly that: a spectacle. Police jogged with German shepherds and drove in circles with armored cars adorned with Tunisian flags. In Hay Ettadhamen, the neighborhood of the capital where Ansar Al-Sharia attempted to move their meeting, it was quite real: Clashes with local Salafists and residents ended with one 27-year-old shot dead.