Israeli Defense Minister Moshe Yaalon, who expressed “sorrow” over Abu Ein’s death, also reiterated Israel's interest in maintaining security ties with the Palestinians.

Abbas, however, has not gone as far as some of his colleagues. In a speech on Dec. 10, the PA leader warned that “all options are on the table,” but stopped short of mentioning the security cooperation in which he's been so heavily invested.

Since its formation in 1993, through the Oslo Accords, the PA coordinated security arrangements with Israel in parts of the West Bank and Gaza, on the understanding that it would police Palestinians in the course of negotiations towards Palestinian statehood that were only expected to take around three years. Israel maintained the prerogatives of the occupying power, deciding the number of personnel and types of weapons allowed in the PA security services — and also the right of its own security forces to operate directly in areas policed by the PA.

The PA forces were responsible for restraining attacks by Hamas and other groups opposed to the Oslo Accords, and their crackdowns on Hamas helped fuel the intense animosity between the two groups that exploded in the 2007 power struggle in Gaza.

PA security cooperation with Israel unraveled during the second Intifada following the collapse of negotiations, when PA officers joined the fight against Israeli soldiers and police. The U.S. responded by cutting funding to the PA's security forces and supporting Israel's isolation of the PA's then-president, Yasser Arafat.

But following Arafat's death, his successor, Abbas, who believed that the second Intifada was a catastrophic strategic mistake, called for renewed security coordination with Israel. He embraced U.S. initiatives for reform of the PA security sector, and U.S. support and funding for those forces became more important after the electorate in the West Bank and Gaza made Hamas the ruling party in the Palestinian legislature in January of 2006. Hamas took control of Gaza the following year in a violent showdown with security forces that remained under Abbas' control.

In 2007, oversight of the training and funding of PA security forces became the job of a senior U.S. military officer, Lt. Gen. Keith Dayton. At the time, PA forces comprised of 176,000 personnel with the presidential security force making up the largest contingent with 57,000 members. Other forces included civil police, public security, and general and military intelligence. From 2007 to 2010, the U.S. State Department spent nearly $400 million in aiding, training and equipping PA forces.

The PA security sector today employs almost half of the 145,000 people on the PA payroll, and consumes $1 billion of the PA’s $3.9 billion budget — roughly the same amount as health and education combined.

Having been established to police a transition to Palestinian statehood, the PA security forces instead find themselves policing a status quo of continued occupation. In coordination with its Israeli partners, the PA arrests those suspected of organizing actions against Israel, but it is not authorized to act against Israeli settlers who vandalize Palestinian property or attack Palestinians.

Abbas has argued that such arrangements are in the best interest of the Palestinians, but many Palestinians disagree.

“The essence of security cooperation is to detain and arrest any Palestinian who is suspected of or engaged in resistance,” former PLO legal advisor Diana Buttu told Al Jazeera. “There has not been and cannot be any benefit to cooperating with Israel to repress legitimate Palestinian resistance.”

Even Gen. Dayton recognized there was a danger that the forces he was building could be perceived as protecting Israel rather than Palestinians. During a 2009 appearance in Washington, Dayton warned that PA security forces enforced order in the West Bank in the belief that they were securing an emerging Palestinian state. But "with big expectations come big risks," Dayton reportedly told his audience. "There is perhaps a two-year shelf life on being told that you're creating a state, when you're not.”

That was five years ago, of course, and Palestinian statehood is no closer to being a fact on the ground now than it was when he issued his warning.

Despite Abbas facing growing pressure, even from within his own Fatah party, to end security cooperation with Israel, the stakes are high for a PA president who has pinned his entire career on a strategy of accepting U.S. tutelage in the hope that it will lead to Palestinian statehood.

The PA’s budget, especially its security sector, is heavily funded by the United States, Israel’s staunchest ally. When Abbas won acceptance of Palestine as a non-member state at the United Nations in 2012, the U.S. immediately imposed financial punishments, which included blocking $200 million in budgetary assistance. Also, Israel refused to deliver tax and customs revenues it collects on behalf of the PA. Even then, Washington was mindful of the need to sustain the Palestinian security sector because of its role in safeguarding Israel from attack.

“[The PA] continues this cooperation in order to maintain good ties with the U.S. and Israel," Buttu argued. "What Palestinians need is a liberation movement, not a security subcontractor.”

Tariq Dana, assistant professor at Hebron University, said breaking security coordination would put pressure on Israel, but also “undoubtedly harm the PA leadership interests who became increasingly subject to Israeli mechanisms of financial control and political blackmailing.” The PA leadership, he added, "is not willing to confront Israel in such a way.”

After all, Abbas has previously said that security ties with Israel are "sacred," which would mean they're not up for negotiation.