Operation Featherweight: Month 38, Week 1, Day 4.

In August 2014 the Islamic State of Iraq and the Levant (ISIL) overran northern Iraq. This included seizing the city of Mosul which went on to function as ISIL's de facto capital within Iraq.

On October 17th 2016 (17/10/16) an operation was launched to liberate Mosul. This was a combined operation.

The Iraqi Kurdish Peshmerga alongside the Iraqi Popular Mobilisation Forces (PMF) militias would secure the areas around Mosul while the Iraqi Security Forces (ISF) would liberate the city itself. All aspects of the operation were supported by the US-led coalition - Combined Joint Task Force: Operation Inherent Resolve (CJTFOIR).

The critical flaw within the plan to liberate Mosul was that the entire western side of the city was left undefended. Dubbed; "The Falls Road" this was done at former US President Barack Obama's request in order to ensure a quick victory by allowing ISIL fighters to flee back into Syria.

The problem with this idea is that if ISIL fighters were able to flee to Syria they were also able to flee to Turkey. From Turkey ISIL fighters would be able to travel on to places like Europe, Libya and Afghanistan.

Fortunately the PMF were alive to this threat. On October 29th 2016 (29/10/16) they opened a front to the west of Mosul to seal the Falls Road. This was done by advancing from the Qarrrayh Front south of Mosul to the town of Tal Afar which sits about 80km (48 miles) west of Mosul on the H47 Highway between Mosul and Iraq's border with Syria.

The sealing of the Falls Road was completed on November 16th 2016 (16/11/16) with the PMF liberating Tal Afar Airport which sits around 7km (4 miles) south of Tal Afar itself. This established the The Qarrayah-Tal Afar Line.

On February 26th 2017 (26/2/17) the PMF along with the ISF's 9th Armoured Division moved to tighten the western cordon on Mosul. They did this by advancing from the town of Tal Zalat around 20km (12 miles) west of Mosul to the town of Badush around 12km (7 miles) north-west of Mosul.

The establishment of this Tal Zalat-Badush Line was completed on March 26th (26/3/17). It is this which allowed the ISF's 9th Armoured Division to open a northern axis within western Mosul.

The PMF then turned their attention to liberating everything between the Qarrayah-Tal Afar Line and Iraq's border with Syria.

This was completed on June 7th (7/6/17) with the liberation of the border village of Tal Safuq. It saw the PMF liberate some 28,000kmsq (16,800milesq) of territory including the ancient city of Hadar/Hatra and the now infamous town of Sinjar/Shingal along with the H47 Highway between Tal Afar and Syria.

The problem has always been Iraq's neighbour to the north, Turkey. It's President/Prime Minister/Emperor Recep Tayyip Erdogan has forbidden the PMF from moving ahead to liberate Tal Afar itself. Erdogan has deployed troops to Turkey's border with Iraq and threatened to invade if the PMF entered Tal Afar.

Apart from his support for ISIL Erdogan's opposition to the liberation of Tal Afar is that it's population is predominately made up of ethnic Turks.

The Turkmen as they're known are a mixture of Sunni and Shia Muslims. The prospect of the predominately Shia PMF liberating these Turkmen from the nominally Sunni ISIL could well lead to Sunni Erdogan losing vital support in an area he one day hopes to annex as part of his new Ottoman Empire.

On July 9th (9/7/17) Mosul itself was liberated. This obviously included the area between Mosul and Tal Zalat-Badush line.

Since then the ISF have been redeploying its forces to reinforce the PMF in preparation for an operation to liberate Tal Afar.

As of August 15th (15/8/17) they had taken up positions at several locations at the edge of the Tal Afar municipal area;

To the east of Tal Afar the ISF/PMF positioned themselves around the town of Al Buwayr. This sits around 30km (18 miles) east of Tal Afar just south of the H47 Highway/M1 Motorway linking Tal Afar to Mosul.

To the west of Tal Afar the ISF/PMF positioned themselves just outside the town of Ibrat ash Shaghirah. This sits around 20km (12 miles) west of Tal Afar just north of the H47 Highway linking Tal Afar to Sinjar/Shingal.

To the south-east of Tal Afar the ISF/PMF positioned themselves around the town of Ayn al-Jahesh. This sits around 55km (30 miles) south-east along the Zambar-Ibrahim Mountain.

On Sunday (20/8/17) the operation to liberate Tal Afar was begun.

The first stage was to reach Tal Afar itself by liberating all the villages and farms in the municipal area. This includes a largely uninhabited area to the north of Tal Afar. That area includes the Camp Numaan military base and the Kasik Oil Refinery.

On that first day of operations the south-eastern axis advanced some 30km (20 miles) amid heavy resistance to liberate the village of Muhallabiyah at the foot of the Zambar-Ibrahim Mountain.

The eastern axis advanced some 15km (10 miles) to liberate the village of Qaryat al-Ashiq at the junction where the M1 Motorway becomes the H47 Highway.

The western axis liberated Ibrat ash-Shaghirah and pressed on to Tal Afar.

On the second day of operations (21/8/17) the eastern axis liberated the Camp Numaan base. The western axis entered Tal Afar itself and liberated the al-Nour district. This sits on the north-west side of the H47 Highway as it runs through Tal Afar.

Today (22/8/17) the eastern axis has liberated the Kasik Oil Refinery. The western axis has entered al-Kazraa district of Tal Afar. The south-eastern axis has liberated the village of al-Tinyah just north-west of Muhallabiyah.

Obviously there is something you don't say at the start of a battle.

However it is worth pointing out that Tal Afar is significantly smaller than Mosul. The estimated 2,500 ISIL fighters there have been totally besieged for five months.

17:45 on 22/8/17 (UK date).