The extremist settlers call it "Price Tag." We have always called it by its proper name: Terrorism.

Now, Israel's Shin Bet, the IDF's top brass and Israeli Cabinet members agree with us. On Monday, shortly after a mosque was torched in an Israeli-Arab village in the Galilee and "Price Tag" graffiti was found nearby, Internal Security Minister Yitzhak Aharonovitch, a member of the extreme right wing Yisrael Beitenu Party, told an Israel Radio reporter that he prefers not to use the perpetrators self-serving jargon. "This is an act of terrorism," he said.

The problem is that largely because of law enforcement negligence, a terror campaign that has been raging in the West Bank for at least three years, has now mushroomed into a widespread phenomenon - both in the West Bank and in Israel proper - that targets not only West Bank Palestinians but also Israeli Arab citizens, Israeli peace activists and Israeli law enforcement officers.

"Price Tag," also known among its perpetrators as "Arvut Hadadit" (Mutual Responsibility), started out as a violent tactic employed by young militant Israeli settlers in the West Bank to deter Israeli law enforcement authorities from removing illegally-built structures from West Bank settlements and illegal outposts. The tactic includes attacks on Palestinians and their property, as well as attacks on Israeli military and police officers to obstruct and deter law enforcement inside settlements.

This tactic was born out of a sense of frustration among some settlers following their leadership's inability to stop the Disengagement from the Gaza Strip in 2005. It gradually became a popular - and very effective - low-intensity anti-Palestinian terrorism campaign. It has recently been creeping into Israel, and is therefore increasingly viewed as a real danger by the security authorities. Israeli law enforcement authorities tend to be more tolerant of anti-Palestinian violence in the West Bank than they are of violence inside Israel. As often happens, what was tolerated in the West Bank has crossed the Green Line, and is now plaguing Israelis inside Israel.

In the West Bank, extremist settlers have for years tweaked and perfected this terrorism tactic and have been successful in achieving two major objectives. First, they have deterred Israeli authorities from enforcing the law and demolishing illegally-constructed buildings in West Bank settlements. Second, they have done so without alienating the average Israeli who lives inside the Green Line and doesn't really care much about the settlers or the Palestinians. The settlers' "Price Tag" campaign has been a major success and a rather unique form of terrorism in Western experience: Politically-motivated violence, directed against innocent civilian members of an adversarial society (Palestinians), with a primary purpose of deterring the terrorists' own government (Israel's) from taking actions against their community.

Violent attacks by settlers against West Bank Palestinians are not a new phenomenon. They date back to the early years of the settlement enterprise. And, of course, deadly Palestinian violent attacks against the settlers are not new either. What was new when the settlers initiated their Price Tag campaign about three years ago was the use of violence by the settlers not only to influence the behavior of the Palestinians, but also - chiefly - to influence the behavior of the Israeli government.

It is impossible to comprehend the roots of this campaign without examining the traumatic impact that Israel's August 2005 withdrawal from the Gaza Strip and from four settlements in the northern West Bank had on the settlers. The "Gaza Disengagement" traumatized the settlers in several ways:

•The settlers' public perception and self-perception as a paper tiger - The eviction of settlers from Gaza - about 8,500 people - lasted eight days, and was carried out with mild resistance from the settlers. It was anti-climactic. It followed a protest campaign by settlers and their sympathizers inside Israel that lasted ten months and included mass demonstrations and two murderous attacks by Israeli Jewish terrorists against Israeli Arabs and Palestinians, all in an attempt to derail the government's disengagement plan. The settlers resisted the eviction from Gaza, but failed to mobilize a mass civil disobedience campaign and a broad conscientious objection campaign among Israeli soldiers. Israeli law enforcement authorities were successful in quickly and efficiently evicting the settlers and in dismantling the settlements in Gaza, a feat that deeply alarmed the settlers. They were concerned that the precedent would encourage Israeli leaders to withdraw in the future from most - if not all - of the West Bank.

•The settlers' failure to capture the hearts and minds of most Israelis - The disengagement, at the time, was popular. Almost two thirds of Israelis supported it. Of those who did not, only a minority opposed it on ideological grounds, on the grounds that portions of the Land of Israel should not be compromised.

•A generational rift between the settlers' older "traditional" leadership and the young activists - The battle against the disengagement was a failure. The intense public relations campaign that the settlers' traditional leaders carried out over the course of almost a year, attempting (in their words) to "settle in the hearts" of Israelis, using "positive" slogans such as "we have love, and it will triumph," did not work. At the conclusion of this charm offensive, most Israelis sided with Prime Minister Ariel Sharon's drive to uproot the settlers from their homes. Sympathy for the settlers was at an all-time low. The young activists accused the traditional leaders of creating a situation that would make future withdrawals from the West Bank much easier for the government to implement. Indeed, leaders of Ariel Sharon's ruling Kadima party were openly talking about future plans to withdraw unilaterally from vast parts of the West Bank, uprooting thousands of settlers. Indeed, this was the key plank in the Kadima party platform in Israel's March 2006 general elections. Ehud Olmert ran on this platform and won.

Shortly before the elections, in February 2006, the settlers were handed an opportunity to change course. The government was preparing to enforce the law and dismantle several houses at the illegal outpost of Amona, not far from the Palestinian town of Ramallah, north of Jerusalem. An illegal outpost is a settlement - typically a small one - built without Israeli government authorization, in violation of Israeli law.

Although the demolition in Amona was of only nine houses - a fraction of the buildings vacated and demolished in the settlements of the Gaza Strip several months earlier - the settlers' leaders prepared for a major confrontation. This time, the leaders were not of the older generation - rabbis and activists who established the settlements in the 1970s and 1980s - but young activists, who rejected the rabbis' reticence in confronting the state establishment. Young leaders amassed thousands of activists, also known as "the Hilltop Youth," who violently clashed with a large force of Israeli police officers, pelting the officers with rocks, bricks and metal bars. Hundreds of settlers were injured, as well as scores of police officers, many more than those injured during the Gaza Disengagement, months earlier.

The settlers' violent conduct in Amona was a direct reaction to the Gaza Disengagement trauma. At the time, Yuval Diskin, then chief of the Shin Bet, Israel's secret service, said: "the motivation of the people in the field was to make up for the disgrace of Gush Katif [the main bloc of settlements in Gaza - O.N.] and to drive a message: Not through love we will triumph, but through struggle and war."

At a February 5, 2006 cabinet meeting, Diskin warned the ministers that he was witnessing a "process of rift" between the settlers and the state. He noted that some of the settlers in Amona had carried signs that read: "In war we will prevail," and "It is Jews who build and Israelis who destroy."

Initially, the settlers and their supporters perceived the Amona experience as a disaster. They came out of it bloodied - both physically and figuratively. Violent resistance didn't prevent the demolition of the illegally-built houses in Amona, violent confrontation with Israeli law enforcement further alienated the Israeli public, and the rift between their traditional leaders and the young activists deepened.

But with time, the perception of Amona as a defeat was transformed. More than a year after the battle, Knesset Member Uri Ariel, one of the ideological settlers' leaders, published an article in the national-religious daily Hatzofe headlined "A Defeat That is All Triumph."

The main reason for that "triumph" was that the settlers did achieve one fundamental goal: They kept Israel's government - for more than a year - from carrying out more demolitions at illegal outposts. The government knew that any further implementation of demolition orders would cause more bloodshed. Internal police probes and other investigations showed that much of the bloodshed was a result of police and the army using excessive force.

In his article, MK Ariel wrote: "The fact that since Amona not even one outpost has been uprooted...stems directly from the fact that the form of the battle in Amona has presented the military and the police with an intolerable price-tag." The experience has "deterred the military and police establishment," Ariel wrote. He called for "leveraging the Amona events" to prevent them from reoccurring.

That was exactly what the "Hilltop Youth" did. They used the Amona lessons to escalate their deterrence campaign.

And as a result, over the past four or five years, whenever Israeli military and police officers arrive at a settlement or illegal outpost to carry out demolition orders, local young activists gathered to resist. If homes were demolished, settlers would avenge the action by attacking Palestinian property or by disrupting traffic. At first, they also attacked police officers and soldiers, but before long, they focused on attacking Palestinians, a modus operandi that won them back significant support from the Israeli public. Physical attacks against soldiers and police officers continued, but were not the focus of the settlers' resistance.

About a year after the Amona events, when the Olmert government launched a selective, timid initiative to demolish illegal structures in settlements and outposts, the Hilltop Youth and other settler leaders organized efforts to resist. They called it "Mutual Responsibility" (Arvut Hadadit, in Hebrew - a term that denotes a Jewish value of caring for each other within the community).

The idea was prosaic, according to one of the Hilltop Youth's leaders. In an anonymous May 2011 interview with the Israeli daily Yedioth Ahronoth, this leader explained that some families whose homes had been demolished were absent at the time of the demolition and were thus unable to resist. "One evening, about three years ago, a few people sat in a small settlement in Samaria [the northern West Bank - O.N.] and looked for a solution. The IDF would demolish settlement outposts without a response, because people simply weren't able to reach the [sites slated for] evacuation," he explained. "So for these people, who did not have the privilege to oppose the demolition, the concept of 'mutual responsibility' was born that evening, and later on, the media decided to call it the 'Price Tag.'"

At the time, the settlers' resistance was mainly directed at IDF soldiers and Israeli police officers carrying out the demolition orders. Yitzhak Shadmi, the director of the Samaria Settlers' Council, an umbrella body that represents the settlers of the northern West Bank, put it this way in a June 2008 interview: "Dismantling is for us a crime. And if it is a crime it must be prevented." In reference to the settlers' traditional leaders who advocated avoiding a confrontation with the government and its law enforcement authorities, he said: "Whoever is not preventing it is an accomplice. It is simple logic." He added, "During the struggle, they [the traditional leaders - O.N.] decided that it was inappropriate to defeat the State and the IDF. We think that when the IDF gives orders that are inappropriate, it must be defeated." Asked about future plans, he said, "we will conduct a rough and piercing struggle, and not necessarily in the arena that they are thinking of. The arena will be [determined] according to our consideration."

The settlers have always been sensitive to Israeli public criticism. When such criticism mounted, cognizant of their fellow Israelis' low tolerance for attacks on the IDF, a people's army, the settlers directed most of their attacks against Palestinians and their property.

The United Nations office for the Coordination of Humanitarian Affairs (OCHA) in the West Bank has documented a total of 1,451 settlers' attacks on Palestinians and their property since January 2006: Physical attacks on Palestinians, attacks on vehicles, houses, schools and mosques, uprooting of trees, torching of fields, and more. Even if these attacks weren't all part of "Price Tag," many - probably most - were. The data show a sharp increase since October 2009, when Prime Minister Netanyahu announced his intention to impose a ten-month long moratorium on settlement construction (the Israeli cabinet officially decided to approve Netanyahu's decision in November 2009).

When government demolition attempts intensified, "Price Tag"-related attacks soared accordingly. The following data documenting settlers' attacks against Palestinians and their property, were specially aggregated by OCHA for APN and sent on July 20, 2011:
2006: 162
2007: 149
2008: 271
2009: 216
2010: 417
2011 (January through June): 236

Methods of "Price Tag"-related attacks on Palestinians and their property vary. In most cases, they involve vandalism, damage to property, and typically light injuries to Palestinians. The perpetrators of "Price Tag" attacks have been careful to maintain a relatively low level of violence, albeit widespread. There are several reasons for Price Tag's being a form of low-intensity terrorism:

•Maintaining a high level of Israeli popular support: Extreme violence might alienate the Israeli public. Low-intensity violence creates a "comfort zone" of sorts for Israelis, who often view such violence as a somewhat legitimate form of protest.
•Avoiding accountability: Israel's "Judea and Samaria" police district, responsible for law enforcement in the settlements, is understaffed and under-equipped. It does not have the resources to investigate petty crime such as vandalism. Most Price Tag incidents do not end up with indictments. For example, in 2008, 105 indictments were filed against Israeli civilians for attacking Palestinians and their property in the West Bank. In 2007 the number of such indictments was 61, according to a November 14, 2008 Yedioth Ahronoth report.
•Allowing room for escalation: Cumulative deterrence, the impact that the settlers are hoping to achieve through their Price Tag campaign, is best accomplished on a gradual scale of escalation. The use of limited force to avenge limited-scale house demolitions implies the potential use of greater force in retaliation of greater action.

Israeli security officials reportedly estimate that several thousand young activists take part in the attacks. Young activists reportedly communicate through text messages on their mobile telephones. Typically, the attacks come in retaliation for the demolition of illegal structures in settlements or outposts, or to prevent such demolitions.

In some cases, waves of attacks on Palestinians came in response to political developments, such as the November 2009 decision to freeze settlement construction. In other cases, they came to avenge Palestinian terrorist attacks on settlers -- for example, the wave of attacks on Palestinians following the murder of five family members in the settlement of Itamar, near Nablus, in March 2011. That month set a record: 81 "Price Tag" attacks in one month, according to OCHA data, the highest number of attacks in one month since 2006.

A public opinion poll published on March 28 2011 - as "Price Tag" attacks soared and the Israeli public was still under the effect of the Itamar attack - showed that almost half of the Israeli public (46%) was supportive of "Price Tag" tactics.

While 48% said "Price Tag" attacks were unjustified, 22% said the actions were "perfectly justified", and 23% defined them as "quite justified." While most secular Israelis Jews said they opposed "Price Tag" activities (36% in favor, 57% against), most traditional, national-religious and ultra-Orthodox Jews said they believed these actions are justified (55%, 70% and 71%, respectively).

In other words, among the ideological settlers' natural constituency - national-religious and ultra-Orthodox Israeli Jews - a solid majority expressed support for the tactic. But even among secular Israeli Jews, more than a third expressed support.

It is entirely possible, if not likely, that the timing of the poll influenced the respondents' views. Israelis were still under the influence of the horror of five family members, including young children, massacred in their beds on a Sabbath. But even if one accounts for the impact of the outrage, such significant support for violent actions against innocent Palestinian civilians means that the settlers achieved an important goal. They avoided alienating a very large segment of the Israeli public and galvanized significant support among their natural constituency.

Israel's security establishment has been wrestling for years with the challenge of deterring Palestinian terrorism, and not without success. It has also made a point of not allowing Palestinian terrorists to use the threat of terrorism to thwart or curtail Israel's freedom of action politically. In other words, it has always worked to deny terrorists the ability to achieve a "balance of deterrence."

The settlers' Price Tag tactic has succeeded where Palestinian terrorism has failed. It has successfully influenced the Israeli political and security establishment's short term decision-making and its long term calculations. In the short term, it has deterred Israeli law enforcement authorities from keeping its international commitments, enforcing the law, and demolishing structures built in violation of Israeli law.

In the long term, the Price Tag campaign serves the settlers in building cumulative deterrence. It serves to deter Israel's leaders and the Israeli public from acting to achieve an Israeli-Palestinian peace agreement that would require removing settlers from the West Bank en-mass, by sowing fears of escalation among the Israeli public and government. Israelis, including senior officials, often express some version of the following: If removing a handful of buildings from an illegal outpost sets the settlers off on an uncontrollable rampage, just imagine how bad it'll be if the government signs a peace agreement and commits to removing tens of thousands of settlers from scores of settlements.

In November of 2008, following a wave of settlers' attacks against Palestinians, the head of Israel's secret service, the Shin Bet, again briefed the Israeli cabinet on the radicalization among young West Bank settlers. According to Israeli journalist Alex Fishman (known for his extensive contacts within Israel's security establishment), Shin-Bet Head Yuval Diskin told the Cabinet (as paraphrased by Fishman): "If you don't intend to wield governmental authority and enforce the law without blinking, then don't mess with them, because you will only light unnecessary bonfires. If you don't seriously intend to remove them, then you are powerless to deal with their hooliganism against the Palestinians; don't play into their hands. They are serious. They will yet fire at police, at soldiers, at political leaders."

In so saying, Diskin captured the impact of the settlers' successful campaign of deterrence. The Israeli government indeed got the message, and has acted accordingly. Although the government has continued over the past three years to evict or demolish illegally built structures in settlements and outposts, it has done so piecemeal, and very selectively. It has not demolished any of the 100-odd illegal outposts that have popped up throughout the West Bank over the past decade or so, and it has not cracked down decisively on the Price Tag perpetrators -- thus neither reversing their achievement of effective deterrence, nor preparing the ground for removal of illegal outposts in the future, and certainly not creating an environment necessary for removing settlements in the context of a future peace agreement.

Price Tag has so far been a success story. It is the success of an illegal, terrorist tactic aimed at perpetuating illegal construction and land grabs, and limiting the political maneuverability of future Israeli governments, should they seek to achieve a peace agreement with the Palestinians.

Now that this terrorism campaign has crossed the Green Line into Israel and is threatening to light an ethnic civil war in northern Israel, the Israeli government may finally realize just how dangerous this terrorism is and act decisively to crack down and root out this Price Tag campaign, for the sake of current domestic stability and peace and in order to pave the way for a future Israeli-Palestinian peace agreement.