IDF and Shin Bet (Israel Security Agency) assessments of the level of extremism in some Jewish settlements in the West Bank are not encouraging.According to one official assessment, a few dozen residents of West Bank settlements are prepared to use violence, including gunfire, against Israeli security forces to prevent the evacuation of settlements. In addition to these few, there are hundreds more believed to be prepared to use such violence against Palestinians. A few, the Shin Bet believes, are prepared to target Israeli politicians as well.Whatever the real numbers are, Yitzhar is where the IDF has been getting an almost daily taste of the type of resistance it might face in a future evacuation. While such an evacuation appears to be far off, Israel is hoping to get the Palestinian Authority back to the negotiating table, and the threat will fluctuate according to the progress of the negotiations.A sample of this resistance was felt on Thursday when security forces arrested a number of Yitzhar settlers on suspicion of involvement in attacks against Palestinians. Later in the day, civil administration inspectors arrived to issue a demolition order for a structure that was being built illegally and against the government-imposed moratorium on settlement construction. They were met by fierce violence, which also included a number of attacks on nearby Palestinians.This was not the first time Yitzhar had turned violent. On Independence Day last week, a soldier was assaulted by a group of settler youth after he prevented them from approaching a nearby Palestinian village. In recent weeks, there have also been a number of attacks against Palestinian mosques and cars in towns near the settlement.The instigators and violent Jewish rioters are not actually believed to come from Yitzhar, but are mostly said to be youth who study in yeshivas in the settlement and nearby communities. Like the vast majority of people who live in Judea and Samaria, the residents of Yitzhar are generally perceived to be normative, law-abiding people.Some of the youth who spend time in the settlement, though, are adifferent story. They came of age during and following thedisengagement from the Gaza Strip, and they watched – some firsthand –as the IDF succeeded in evacuating all of the settlements in just sixdays. Their conclusion was that such an evacuation could not be allowedto happen again.Another turning point was the evacuation of the illegal outpost ofAmona in February 2006, when Border Police clashed with settlers assecurity forces demolished nine illegally-built homes. Over 300 peoplewere injured, and the Knesset established a special parliamentarycommittee to investigate police violence.Then, too, however, the settlers failed to prevent the demolitions.These failures are understood by the IDF to be the source of motivationfor the current wave of settler violence. The almost routine clashesnear Yitzhar are an indication that this time, some of the settlersplan to put up a fight.