Following 48 hours of terrorist attacks in France, Lebanon and Iraq, the extremist group calling itself Islamic State of Iraq and Syria (known as IS, ISIS or ISIL) has claimed responsibility for the bombings and shootings that left more than 175 people dead.

The group - a self-proclaimed Islamic state and caliphate - has dominated media reports over the last few years for the countless atrocities they have committed in Iraq, Syria and a number of other countries around the world.

They have also claimed responsibility for the suspected bomb attack on a Russian airliner two weeks ago that left 224 people dead.

Martin Chulov, the Middle East Correspondent for The Guardian, spoke to Shane Coleman on The Sunday Show from Beirut - a city that suffered its fifth attack in the last two years on Friday, killing 45 people and leaving up to 150 wounded.

He discussed the ideologies and beliefs of Islamic State, as well as the factors that have helped lead to the militant group's rapid rise in the Middle East in recent years.

"Motivations range across the spectrum," Martin said on the subject of why so many people - mostly young men - have joined the group. "Most of them seem to be fired by some sense of a divine mission, that what they're doing has been pre-ordained in Islamic texts, and their generation is privileged to be able to carry out these apocalyptic acts on societies whose values they fundamentally oppose.

"They see [these societies] as undermining the literal reading of Islamic text from 1,500 years ago, and seem motivated to fight by force to impose their worldview on our societies," he added.

Martin says not every Islamic State member would necessarily support the manner of attack seen in Paris on Friday. 

"There were several of the senior ISIS members that I've spoken to who don't share a view that attacking people in places of entertainment is a legitimate target," he indicated.

"These are quite senior in ISIS as well. They have told me in the past that no civilian target is appropriate, but military targets are... I can say quite faithfully that these members would not endorse what has taken place [in Paris].

However he pointed out that another member he has spoken to was 'deeply ideological', and believed that anything in opposition to Islam is 'deviant' and an appropriate target.

Martin said it's fair to say that Islamic State's presence in Syria and Iraq has diminished somewhat, despite still having control of an area of land 'roughly the size of Jordan'.

The self-declared caliphate has seen some defeats in recent days, but Martin adds "they still maintain their strongholds in Raqqa and Mosul. If they were to lose either of them, that would be a significant blow for them".

However Martin also mentioned that there are many people "who feel they don't have a choice" other than to join IS, while others have sided with the group despite disagreeing with their ideology and cause.

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