Operation Featherweight: Month 32, Week 1, Day 4.

On October 17th 2016 (17/10/16) an operation was launched to liberate the northern Iraqi city of Mosul from the Islamic State of Iraq and the Levant (ISIL). Mosul has functioned as ISIL's de facto capital in Iraq since the summer of 2014.

This operation is a combined one between the Iraqi Security Forces (ISF), the Iraqi Kurdish Peshmerga and the Popular Mobilisation Forces (PMF) who are a loose coalition of militias that serve as part of the ISF. The operation is being backed by the US-led coalition Combined Joint Task Force: Operation Inherent Resolve (CJTFOIR).

By January 25th 2017 (25/1/17) the eastern half of Mosul - often known as; "The Left Bank" - was fully liberated from ISIL.

On Sunday - February 19th (19/2/17) - an operation was launched to liberate the western half of Mosul - often known as; "The Right Bank" - from ISIL. The first stage of this operation saw the ISF advance in two columns from positions just south of Mosul known as the Qarrayah line.

In this first stage of the advance the main challenge has been to detect and defuse the vast number of landmines and Improvised Explosive Devices (IED's) that ISIL have laid between the Qarrayah line and southern Mosul.

To aid with this the US and other CJTFOIR nations have deployed a number of highly trained bomb disposal specialists to assist the ISF. Yesterday (22/2/17) the US confirmed that a number of its deployed specialists had come under fire and being wounded. However no further details have been given.

By the end of the first day of operations the ISF had liberated 10 villages and the Lazakah power plant which provides power to all of Mosul.

By Monday (20/2/17) evening the ISF had succeeded in liberating the Albu Saif village/neighbourhood which sits at the southern most tip of Mosul's western side. By Tuesday (21/2/17) they had succeeded in liberating Yarmouk village/neighbourhood which sits between Albu Saif and Mosul.

As with Gogjali to the east of Mosul neither Albu Saif nor Yarmouk are technically part of Mosul. However they are so close that on the ground you would need that administrative distinction pointed out to you.

As you move north from either Albu Saif or Yarmouk to your east you have Mosul airport while to the west you have the Ghazlani military base. Together Mosul airport and the Ghazlani military base occupy roughly 20% of the territory on Mosul's western side.

The problem is that the airport and the military base function almost as a city within in a city. So if the ISF were to move to liberate the airport without also liberating the military base ISIL fighters in Ghazlani would cut the ISF troops at the airport to pieces. Likewise if the ISF moved against the military base without also liberating the airport ISIL fighters in the airport would cut the ISF troops in Ghazlani to pieces.

So what the ISF needed to do was take both the airport and the military base at the same time. This requires a lot of careful coordination. As a result on Wednesday (22/2/17) the operation went into a short tactical pause.

The operation resumed at dawn today with dramatic effect. Within four hours the ISF had succeeded in liberating Mosul airport. They also entered the Ghazlani military base and were reported to be in control of at least half of it. However at the time of writing that report was at least six hours old so the ISF may have liberated more of Ghazlani base by now.

Obviously I'll be a lot happier when Ghazlani base is fully liberated. However even 50% control should be enough to suppress the ISIL fighters there and help protect the airport. The test will come tomorrow it seems almost inevitable that ISIL will launch a counter-offensive.

The liberation of the airport and the military base is a huge gain for the ISF. Obviously it means that around 20% of the total territory they need to liberate has been liberated. In a day.

However it also provides the ISF with a base of operations within western Mosul. Once the area has been fully secured they can now bring reinforcements, ammunition, fuel and other supplies into Ghazlani and then quickly supply them to ISF units fighting elsewhere in western Mosul as the operation progresses.

Throughout the Mosul operation the big problem has been the failure to establish a western front to encircle the city on all sides.

This was partially solved on November 16th 2016 (16/11/16) when the PMF completed an advance from the Qarrayah line liberating Tal Afar airport from ISIL. This established a western front cutting ISIL off from Syria. However it still left the problem of what to do about Tal Afar itself.

This entire Nineveh Plains area surrounding Mosul to the town of Sinjar/Shingal around 140km (85 miles) to the west is almost exclusively Sunni-Muslim. However Tal Afar itself stands almost as a little island of ethnic Turks. These Turkmen are a mixture of both Sunni and Shia Muslims.

Although there are around 60 PMF units in total the PMF units active around the Nineveh Plains are almost exclusively Shia-Muslim. As such Turkish President/Prime Minister/Emperor Recep Tayyip Erdogan has long been afraid that if the PMF liberate Tal Afar the particularly Shia Turkmen will ally themselves with the PMF rather than Erdogan. Therefore Erdogan has long threatened to militarily invade and occupy northern Iraq if the PMF enter Tal Afar.

In response the PMF have decided to simply go around Tal Afar.

When the ISF began their advance north to Mosul on Sunday (19/2/17) the PMF also began an advance north-east from the Qarrayah line. Yesterday (22/2/17) the PMF began an advance in three columns north-east around Tal Afar. The objective seems to be that having rounded Tal Afar they will advance south-east to meet those advancing from the Qarrayah line. This will cut Mosul off from Tal Afar and tighten the noose around the west of the city.

Erdogan's threat to invade and occupy northern Iraq is clearly not an empty one. He has already done just that in northern Syria.

Since mid-to-late November 2016 Erdogan's efforts have been focused on the town of al-Bab. This represents a key supply node within northern Syria. It sits around 40km (24 miles) south of Syria's border with Turkey, 30km (18 miles) north-east of Aleppo City and 50km (30 miles) south-west of Manbij which is controlled by the Syrian Democratic Forces (SDF/QSD).

For a town that is only roughly 20kmsq (12 milesq) is area Erdogan's efforts to capture al-Bab have been long and tortured.

Last Thursday (16/2/17) Erdogan declared that the town had been fully captured. This was soon downgraded to Erdogan's forces only being in control of 40% of al-Bab. On Tuesday (21/2/17) Erdogan declared that his forces controlled 60% of the town. Today it's been announced that Erdogan's forces have taken control of the centre of al-Bab and victory has once again been declared.

As with all other aspects of Erdogan's actions in northern Syria today's announcement seems to be a carefully scripted piece of theatre. It was designed to coincide with the resumption of the United Nations (UN) led Geneva Process on Syria.

In the first instance it projects an image of Erdogan's power. It sends the message that Erdogan controls this piece of Syria and will continue to hold it throughout the Geneva Process. That Geneva Process is of course still suffering from its founding flaw that foreign powers can attack and invade Syria in order to get a say in how Syria is run.

The question of what Erdogan will do next once he has captured al-Bab has long been a cause for concern.

Erdogan has long stated that his next objective is to attack the SDF - and the US Special Operations Forces (SOF's) embedded with them - at Manbij. However more recently Erdogan has said that he intends to send his forces a further 500km (300 miles) deeper into Syria to capture the cities of Raqqa and Palmyra. To deter that latter option Russia has established a security line just south of al-Bab. However Erdogan has recently indicated that he would be prepared to violate that security line even if it means direct conflict with Russia.

Obviously the declaration that al-Bab has been liberated pushes all those questions to the fore right at the moment that everybody is meeting in Geneva.

18:25 on 23/2/17 (UK date).

Edited at around 19:55 on 23/2/17 (UK date) to add;

Key to today's complex manoeuvre has been speed. As a result the days events have been extremely fast moving and at times have seemed utterly baffling to outsiders.

Whilst I was writing the above the ISF came out and gave a formal assessment of their progress. They now assess 85% of the Ghazlani military base to be under their control and 50% of Mosul airport to be under their control.

Obviously the report I would have liked to have heard is that Ghazlani and the Mosul airport are both 100% under ISF control. That rapid gain has triggered a collapse in ISIL's ranks, they've all committed suicide and the battle is over.

However I think this situation is actually slightly better. My main concern was that the ISF would get stranded on the open areas of the airports and come under continuous fire from ISIL positions in the airport buildings and at Ghazlani base.

The fact that the majority of Ghazlani base has been liberated makes that less likely. Obviously though I would like to know exactly which bits of the base and the airport have been liberated and which bits remain under ISIL control.

Also today's operations haven't just focused on the Ghazlani base and the airport.

The ISF have also managed enter and liberate the Tall arRayyan neighbourhood of Mosul. This sit directly north-west of the Ghazlani base.

It is also being reported that the ISF have managed to cross the M1 Motorway as it runs beside the Tall ar Rayyan neighbourhood. This has allowed them to establish a foothold within the Hay al-Mamun neighbourhood which sits direct north of the Ghazlani base.