In an August 14, 2022 interview on BBC Arabic (U.K.), Dr. Mousa Abu Marzook, the Head of Hamas's International Relations Bureau, spoke about why Hamas did not participate in the recent Gaza conflict between Israel and the Palestinian Islamic Jihad (PIJ). He said that the decision whether to participate in the conflict or not is not determined according to public demand, and he defended Hamas against claims that it said it has nothing to do with the conflict or that it has abandoned the concept of "Unity of the Battlefields". He explained that not every Israeli assassination is grounds for going to war. He also explained that the "Unity of the Battlefields" concept did not obligate Hamas to fight alongside the PIJ in the conflict, and that it only reflects the idea that Israel "will not succeed" in separating Jerusalem, the West Bank, Gaza, and the Palestinian-Israelis living inside Israel.
Dr. Mousa Abu Marzook: "Whether to participate [in war] or not is not decided according to public demand. There are other considerations that have to do with the war itself.
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"This was an aggression against the Palestinian people, and the resistance fighters retaliated for this aggression. Since it was the Islamic Jihad that was targeted, the retaliation came from the brothers in the Islamic Jihad."
Interviewer: "But in the past, whenever the commanders of Hamas were targeted, the Islamic Jihad would join the fray. We have never heard them say: 'Hamas was targeted, so this has nothing to do with us.' We have never heard such a thing from the Islamic Jihad."
Abu Marzook: "We did not say that this has nothing to do with us. There was no such statement by Hamas, but you do not go to war over every person who is assassinated, regardless of his affiliation. Many of our commanders were targeted and no war ensued."
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Interviewer: "But the relevant party — the Islamic Jihad — decided to retaliate in this case. Whatever happened to the notion of 'Unity of the Battlefields'? Whatever happened to the commitment to help one's brother?"
Abu Marzook: "'Unity of the Battlefields' does not mean what you think it means. It means that the enemy will not succeed in separating Jerusalem from the West Bank, the West Bank from Gaza, or Gaza from the Palestinian [Israeli citizens] within the occupied land. This is the meaning of 'Unity of the Battlefields.'"