In the Islamic State (IS) group, all militants are equal. But some are more equal than others, according to a Daghestani pro-IS preacher.

Kamil Abu Sultan ad-Daghestani has complained that Saudi militants in Iraq are putting their friends and relatives forward for cushy suicide-bombing missions in Iraq, leaving Chechens without opportunities to blow themselves up.

As a result, militants are forced to spend months on the suicide-bomber waiting list in Syria in order to land a "job."

Abu Sultan's complaint, titled Corruption In Dawlah (which is shorthand for IS), was shared on a new website named Qonah. The site is registered to a German Internet provider and appears to be linked to a group of North Caucasus people connected with Akhmed Chatayev (Akhmad al-Shishani), a veteran Chechen militant in charge of IS's Yarmouk Battalion.

Abu Sultan explains in his complaint that he found out about the suicide-bomber problem from Chatayev.

According to Abu Sultan, the waiting list for suicide bombers in Syria is so long that -- ironically -- some militants die on the battlefield before they get their chance to explode for IS.

The Syrian suicide-bomber backlog has pushed some militants to go to Iraq, where there is a much shorter waiting list.

"Amir [Leader] Akhmed al-Shishani told me about a young lad who went to Iraq for a suicide mission, and he went there because in Sham [Syria] there is a veeeeery long queue [of several thousand people]," Abu Sultan wrote.

But when the young suicide-bomber wannabe got to Iraq, he found that he still was unable to blow himself up.

After three months with no suicide bombing, the young militant gave up and came back to Syria, according to Abu Sultan.

Saudi Nepotism

The would-be suicide bomber complained that the only way to get a suicide-bombing assignment in Iraq is through what is known as "blat" -- a Russian slang term meaning connections.

It was Saudi militants in Iraq who were being nepotistic, favoring their family members by pushing them to the top of the suicide bomber waiting list, the militant said.

Abu Sultan writes that the militant went to see Chatayev to complain about the Saudis.

"Those Saudis have got things sewn up, they won't let anyone in, they are letting their relatives go to the front of the line using blat," the frustrated militant told Chatayev.

Abu Sultan said that the way forward to deal with the corruption over suicide bombings was to go straight to the top.

"Well, what I say is, things can't be left as they are, we should complain to the caliph," Abu Sultan opined, in a reference to IS leader Abu Bakr al-Baghdadi.

Abu Sultan did not mention the issue of suicide-bomber corruption, however, in a recent post on the Russian social-networking site VKontakte, where he said that the son of Baghdadi's second-in-command had carried out a suicide bombing and that Baghdadi's own brother had "become a martyr."

"In spite of everything, while we have such leaders, Allah will not allow this state [IS] to be humiliated," Abu Sultan wrote.

Waiting Lists

That would-be IS suicide bombers are placed on a waiting list was revealed in July 2014 by British militant Kabir Ahmed.

Ahmed, who went by the nom de guerre Abu Sammyh Al Brittani, told the BBC's Panorama program that he was on the waiting list to blow himself up.

The 32-year-old father of two, who was in Syria at the time, said he was trying to "get his name pushed up the list" of would-be suicide bombers.

Evidence suggests, however, that Ahmed had to go to Iraq to fulfill his suicide-bombing dream: In November, Ahmed blew himself up in a truck bombing in Baiji. Apparently, Ahmed's road to "martyrdom" was not blocked by nepotistic Saudi militants.

Australian teenage militant Jake Bilardi also went to Iraq to carry out a suicide bombing in Ramadi in March. The 18-year-old only had to wait a few months for his opportunity, however: In January, Bilardi explained that he was on a waiting list with 12 other wannabe bombers.

A recent IS guidebook for potential recruits also advises that those who sign up to be suicide bombers have to be patient.

Before being eligible to blow themselves up, rookie militants go through boot camp.

Afterwards, the guidebook says, "if they want to do a martyrdom operation, they are put in [sic] a waiting list."

Why Are Suicide Bombers So Prized?

Why do IS militants view "martyrdom operations" -- suicide bombings -- as being better than simply dying in battle? After all, both involve a militant giving his life for the sake of IS's military advancement.

The main reason is likely that suicide bombings, particularly truck bombings or vehicle-borne improvised explosive devices (VBIED), offer considerable tactical advantage.

A militant who carries out a suicide truck bombing will have a far greater and more spectacular impact than a foot soldier who is killed on the battlefield.

"In my view, the tactical advantage of suicide VBIEDs [vehicle-borne improvised explosive devices] largely outweighs their symbolic or propaganda value, hence IS's heavy reliance on them," says Syria expert Thomas Pierret of the University of Edinburgh.

Suicide truck bombings enable IS to carry out large-scale detonations using a ton or more of explosives, and with pinpoint accuracy.

"That's a combination you only find with advanced weapon systems that are incomparably more expensive and, anyway, unavailable to nonstate actors so far," Pierret added.

For this reason, IS (and Syrian Al-Qaeda affiliate Jabhat al-Nusra) has used suicide truck bombings to penetrate fortified structures and overwhelm enemy troops.

Most recently, IS used VBIEDs in its assault on the city of Ramadi in Iraq's Anbar Province, targeting military positions in the city with six truck bombs and a bulldozer in a massive assault.

-- Joanna Paraszczuk