He had placed the photograph on his Facebook page of Moataz Hejazi, the terrorist killed by police after shooting Yehuda Glick outside the Begin Heritage Center last Wednesday.
A few days before Abdur Rahman Slodi got into his car and mowed down three-month-old Chaya Zissel Braun and a dozen other pedestrians two weeks ago, PA Chairman Mahmoud Abbas exhorted the Palestinians to prevent Jews from visiting the Temple Mount, Judaism's holiest site, by all means possible.
Slodi had served time in prison for terrorist offenses and was active on social media where he expressed murderous hatred for Jews and a desire to kill them.
So yes, the writing was on the wall. But unfortunately, the writing is on all the walls, or Facebook walls. It is not at all clear how Israeli security services could have known to distinguish these men from the thousands of other Palestinians and Jerusalem Arabs who hate Israel, support the murder of Jews and identify with various terrorist organizations.
On Thursday security forces arrested several people in villages around Hebron with suspected ties to Akary. So he may not have been acting on his own. But all the same, neither he nor Slodi seem to have been directed to carry out their attacks by a cell commander who himself was directed by a higher level terrorist operative.
Rather, in all likelihood, something triggered both men to carry out attacks in a wholly independent or semi-independent manner.
The question is, what was the trigger and how was it pulled? The Israeli media are obsessed with the question of whether or not we are experiencing an third Palestinian terrorist onslaught, or intifada. Public Security Minister Yitzhak Aharonovitch insists that we are not. Others insist that we are. Whatever we want to call it, we are seeing a new form of Palestinian terrorist warfare against Israel, which in many key aspects mimics the larger jihad carried out by al-Qaida and its affiliates and spin-offs.
In a recent article in the online Small Wars Journal, Maj. Nicholas Pace from NATO's Joint Forces Command discussed how al-Qaida and Islamic State have decentralized their terrorist networks.
Due to the superior signals intelligence fielded by the US, Pace explained, al-Qaida and Islamic State have diffused and decentralized their networks into smaller hubs that operate independently.
The role of terrorist chiefs like al-Qaida leader Ayman al-Zawahiri is to inspire and incite, and to a degree direct, operations, rather than plan and order them.
Today the main factor unifying al-Qaida and Islamic State and their sister groups and followers in the region and worldwide is ideology.
They all share the same hatred of the West, of all religions other than Islam and of all competing forms of Islam. They all seek the establishment of a global caliphate that will rule the world under the banner of Islam.
As Pace notes, this shared ideology was all that US Army Maj. Nidal Malik Hassan needed to feel that he was a member of al-Qaida when in 2009, after have a few Internet communications with al-Qaida ideologue Awar al-Awlaki, he walked onto the Fort Hood military base in Texas and massacred his fellow soldiers.
Pace argues that Islamic State forces in Iraq and Syria also operate along a decentralized model of operations, and the more they are directly targeted by the US and its allies, the more they will decentralize and compartmentalize their force structure.
The operational advantage of this model is that it gives enormous flexibility and independence to operatives in the field to maximize their resources. The drawback is that those resources tend to be less sophisticated than those that can be brought to bear by a centrally organized and resourced military organization.
But this isn't really a problem for jihadists.
As Pace notes, they see themselves as soldiers in a long-term struggle. Their goal is not necessarily to conquer their target populations. Rather they seek to make life impossible for target societies.
Mass chaos sowed by constant, low intensity, near-scatter-shot attacks can over time be sufficient to break the will of a targeted society or military organization to fight them.
Certainly this has been the case for the Iraqi military that has melted away in the face of Islamic State's fanatical troops.
For such a decentralized military system to work, the leadership needs two things: a shared ideology, and communications capabilities that enable them to incite and loosely directly violence.
Ideology is not something that people pick up or discard quickly or easily. For a person to be attracted to the jihadist cause he has to undergo indoctrination over a significant period of time.
You cannot incite a person to strike if he hasn't already been indoctrinated in a manner that makes him amenable to your incendiary call to action.
And this brings us back to the Palestinians and the trigger for the attacks conducted by independent or semi-independent terrorist operatives.
With the exception of Pakistani students in madrassas, few societies have undergone the mass indoctrination that the Palestinians have undergone over the past 20 years of Palestinian Authority rule. From the cradle to the grave, and most significantly in the school system, Palestinians are indoctrinated to hate Jews and seek the violent destruction of Israel. They are told that it is an Islamic duty to fight Jews and destroy Israel.
This is as true in regular PA schools as it is in schools run by the United Nations Relief Works Agency (UNRWA).
We are experiencing today in Jerusalem a decentralized terrorist campaign rooted in the 20-year indoctrination of the Palestinians.
Yes, Hamas and Fatah still operate terrorist cells and units that are members of terrorist hierarchies.
But at the same time, they have used a model similar to al-Qaida's in developing semi-independent and wholly independent networks of operatives and operational cells. These independent cells are highly motivated and are willing to wait until they receive generalized signals from their leadership to strike.
So it was for instance in June with the kidnapping and murder of the three teenagers in Gush Etzion. A few weeks before the kidnapping took place, from his home in Qatar, Hamas chief Khaled Mashaal remarked that Hamas needed more hostages to trade for jailed terrorists.
The terrorists in Hebron were motivated to strike. With the financial assistance of Saleh al-Arouri, the Hamas ideologue and operational commander in Turkey, they were able to purchase what they needed for the kidnapping. And when Mashaal said the time had come to kidnap Israelis, the countdown to the kidnap and murder of Naftali Fraenkel, Gil-Ad Shaer and Eyal Yifrah began.
The cell was isolated and tiny. Mashaal's order was indirect.
In the case of the violence in Jerusalem, indoctrination in UNRWA schools in places like Shuafat refugee camp where Akary lived, not to mention throughout Judea, Samaria and Gaza, has raised generations of Arabs who hate Israel and Jews.
Owing to this indoctrination, when presented with mass incitement by preachers in the mosques, and most importantly by the official Palestinian Authority media, these calls for violence are immediately embraced on a massive scale. Indeed, the comfort level that the Arabs of Jerusalem feel today in supporting terrorism may well be unprecedented.
For instance, until this Wednesday night, every time terrorists in Jerusalem used motor vehicles to murder Israelis, their families and neighbors insisted that they were not terrorists but hapless drivers. There had been no attack, merely a traffic accident.
On Wednesday night when reporters went to interview Akary's family and neighbors, they were met by shouts of praise for his murderous act. He was embraced as a martyr. And just as important, his act inspired mob violence in Shuafat and other Arab neighborhoods against police forces. For the first time, support for terrorism outweighed concern about alienating their Jewish neighbors or forcing police retaliation.
On Thursday Fatah's Facebook page was full of images calling for Palestinians to run over Jews.
As Palestinian Media Watch reported, one used a play on words between the Arabic acronym for Islamic State and the Arabic word for running something over, thus positively associating the terrorists who run over Jews with members of Islamic State.
Hamas -- Fatah's partner in the PA's coalition government -- was similarly quick to praise Akary and call for more such attacks.
In dealing with this burgeoning, decentralized terrorist campaign, aside from taking action to protect bus stops with various barricades, Israel needs to go after the triggers.
It needs to break up the indoctrination system.
And it needs to destroy the Palestinian leadership's ability to communicate their incendiary messages.
Since UNRWA schools operating in Jerusalem engage in anti-Semitic indoctrination, Jerusalem municipal authorities must give them the choice of using Israeli textbooks or shutting down. If Israel wishes to assert its sovereignty, UNRWA schools would be a good place to start. Beyond that, preachers in mosques who incite murder and call for the destruction of Israel should be arrested.
As for the PA's communications networks, all of the radio and television signals operating in the PA come from the Israeli electromagnetic spectrum. It is time to shut them down. As Prime Minister Benjamin Netanyahu reiterated on Wednesday, Abbas is directly inciting the murderous attacks on Jerusalem through the PA media organs. The way to protect Jerusalem is to remove him and his Hamas partners from the airwaves.
There has been a lot of talk over the years about providing positive and negative incentives to convince the Palestinians not to engage in terrorism.
But now is not the time for incentives. The population mobilized through incitement has become too fanatical to engage with reason.
The terrorists who take the wheel and run over pedestrians know that they will more than likely never come home. And they don't care.
They certainly don't care that Israel will destroy their homes. And they also certainly won't be impressed by discounted mortgages if they integrate into Israeli society.
In the long term, it is imperative that Israel provide incentives to both the Jerusalem Arabs and the Palestinians to integrate peacefully with Israeli society. But before the government can seriously engage in this task, it needs to destroy the triggers of this terrorist onslaught. It is not enough to complain about Palestinian indoctrination and incitement. It is time for Israel to end them.