Palestine lit festival apparently a threat to Israeli national security

Laila Lalami called my attention to the fact that the opening event of the Palestine Festival of Literature was targeted by the Israeli authorities. This is the second edition of the festival, which brings writers from around the world to do readings and panels in Palestine. Here's what happened, according to the Guardian:
Shortly before the opening event was due to begin, a squad of around a dozen Israeli border police walked into the Palestinian National Theatre, in East Jerusalem, and ordered it to be closed.

Police brought a letter from the Israeli minister of internal security which said the event could not be held because it was a political activity connected to the Palestinian Authority.

Members of the audience and the eight speakers were ordered to leave, but the event was held several minutes later, on a smaller scale, in the garden of the nearby French Cultural Centre.

Israeli police were deployed on the street outside.

Do check out the video, which shows the event being shut down and relocated--as well as the attendees spending most of their first day waiting at Israeli check points. 

(And just wondering--since when is being a political event or being sponsored by the PA enough to get an event shut down? I thought the PA was Israel's negotiating partner? I thought Israel was a democracy?)