Why we should worry about Turkey's fight with IS

Representatives from all 28 countries that make up NATO are met in Brussels Tuesday to discuss Turkey and its decision to join the fight against terrorist group Islamic State in Syria.

CNBC takes a look at the factors that could have prompted the country to join the fight against the jihadists.

Late last week, the Turkish government joined the U.S. in launching air strikes against Islamic State, the terrorist organisation and self-styled caliphate battling for control of vast swathes of Iraq and Syria.

The gains made by the group the group -- formerly known as the Islamic State of Iraq and the Levant (ISIL, or ISIS) -- in both these countries prompted the U.S. and other western allies last year to begin air strikes against the jihadist group.

In Syria, IS is fighting on two fronts: against Syrian soldiers loyal to President Bashar Al-Assad and Kurdish militants who are trying to gain control of parts of northern Syria. Turkey opposes both IS and the Kurdish PKK (Kurdistan Worker's Party), which has been fighting a long-running separatist conflict with the Turks.

Read More Could Islamic State's 'looting economy' face defeat?

Last Friday, Turkey conducted its first airstrikes both on IS positions and those held by the Kurdish fighters. Turkey has also allowed the U.S. to use one of its air bases to launch strikes against IS.

Turkey and the U.S. are also planning to sweep IS fighters out of a strip of land on the country's border with Syria in order to establish an "Islamic State-free zone."

The NATO meting to hear Turkey's request to discuss the campaign against IS and Kurdish militants and the crisis on the country's border. The meeting's delegates gave Ankara its full political support in fighting militants in Syria and Iraq but several nations urged Ankara not to undermine the Kurdish peace process by using excessive military force, Reuters reported.

"Turkey requested the meeting in view of the seriousness of the situation after the heinous terrorist attacks in recent days, and also to inform Allies of the measures it is taking. NATO Allies follow developments very closely and stand in solidarity with Turkey," NATO said ahead of the meeting.

Turkey has long appeared a reluctant to join the fight against IS because of its somewhat vulnerable position on the outskirts of the Middle East – Turkey is often seen as the country that "bridges" Europe, to the west of Turkey, and Syria, to the east.

One factor for Ankara's past reticence could be Islamic State's opposition to the Syrian government has suited Turkey. It is also reluctant to accept more Syrian refugees, as around 2 million people have already crossed the border into Turkey.

Read More Turkey: Why coalition talks could hit its economy

It is also reluctant to help any cause that could empower and strengthen the Kurdish cause. There are believed to be up to 25 million Kurds in Turkey, making any empowerment of that community – despite IS being a common enemy – a controversial move.

What likely prompted Ankara's decision to join the fight against was the recent suicide bombing in Suruc, close to the border with Syria, by a female jihadist believed to be a member of Islamic State, in which 32 people were killed -- and over 100 injured.

This was the catalyst for Turkey's involvement, Ian Bremmer, president of risk consultancy Eurasia Group, said in a note Monday, as Erdogan faced growing calls to act.

"This event was a watershed moment for the Turkish government, leading to anti-government protests across the country," Bremmer said.

While the PKK held the Turkish government responsible for the suicide attack, saying it had 'supported and cultivated' Islamic State against the Kurds, President Erdogan responded to the suicide bombing by launching raids and arrests on hundreds of suspected members of both IS and the PKK in Turkey.

There is the widespread belief that in return for Turkey's agreement to join the fight against IS, the U.S. will "turn a blind eye to Turkish attacks on the PKK in northern Iraq," Ayham Kamel from Eurasia Group said in a note Monday. It will also make the PKK a less useful tool in the fight against IS, he said.

If the fight against IS was not enough, Turkey is struggling domestically with a fractious political environment and lack of government after inconclusive elections in May. Although coalition talks are continuing, the possibility of new, early elections is still high.

Turkey's involvement in the battle against IS could make the country vulnerable – both from within and without.

For example, the PKK has already launched a series of attacks in Turkey after Friday's raids – meaning the end of a fragile ceasefire between the two sides since 2013.

Analysts agree that Turkey has suddenly become far more vulnerable to further attacks.

"Turkey's sudden decision to take the fight to Isis will likely lead to significant successful Isis attacks within Turkey, the biggest shift in terrorist vulnerability for a major emerging market since the beginning of the Arab Spring," Eurasia Group's Bremmer said.

Read More Turkey's election: What happens now?

"That in turn will put a damper on investor sentiment for the country, and make the political process in Turkey that much more challenging."

That view was echoed by Wolfango Piccoli, managing director of risk consultancy Teneo Intelligence, who said in a note on Monday that civil unrest in Turkey was likely to rise.

"Ankara's recent adoption of aggressive policies towards both the Kurdish Workers' Party (PKK) and the Islamic State (IS) has considerably raised the risk of terrorist attacks and sustained civil unrest inside the country," Piccoli warned.

"Amid continued speculation that the ruling Justice and Development Party (AKP) may call an early election for November 2015, there appears little prospect of the country enjoying political stability in the foreseeable future."

- by CNBC's Holly Ellyatt, follow her on Twitter @HollyEllyatt. Follow us on Twitter: @CNBCWorld

More From CNBC

• Top News and Analysis
  

• Latest News Video
  

• Personal Finance