Hamas announced last week choosing Sinwar, its top official in Gaza, as the new leader of its political bureau following Ismail Haniyeh’s assassination by Israel in Tehran on 31 July.

Former head of the Captives and Missing Persons Division in Mossad Rami Igra said Sinwar has gotten "stronger and was appointed as all-powerful in Hamas."

“The things he wanted to happen are happening," Igra noted in an interview with Israeli Radio 103FM on Sunday.

"As long as Israel does not provide a real governing alternative to Hamas in Gaza, then Hamas is in control, and Sinwar proved this by the very fact that he was appointed head of the political bureau,” he added.

Israeli Prime Minister Benjamen Netanyahu “agreed to a horrible deal because of public and international pressure,” according to Igra. 

"The deal as it is about to take place means that Israel will get very few of the captives back alive, thus, returning Hamas to be sovereign in Gaza," he stated.

Israel’s assassination of long-serving Hamas leader Haniyeh has caused the resistance movement to reshuffle its cards, drawing on the institutionalized frameworks already in place and understanding the urgency of a smooth transition.

Sinwar, 61, is one of the main figures Israel vehemently seeks to target.

He had been sentenced to four life sentences and spent 22 years in Israeli prisons. Sinwar was one of more than 1,000 Palestinian detainees who were released in 2011 in exchange for Israeli soldier Gilad Shalit.

Observers believe that choosing Sinwar as the leader of the resistance movement is in itself a warning message to Israel.

 Behind the scenes
 

After Haniyeh’s mourning ceremony in Doha, Hamas veteran faces and shadowy figures held meetings for two days in the Qatari capital, which has hosted Hamas’ political bureau since 2012, to elect a new leader for the group, BBC revealed in a report on the behind scenes of choosing Sinwar.

Sinwar has already been the group's leader inside Gaza since 2017.

According to BBC, the choice of Sinwar may have come as a surprise to many, but anyone following his career since Israel released him in 2011 knew he was always likely to lead Hamas one day.

No political leader in Hamas has ever been closer than him to Al-Qassam Brigades, the group's armed wing.

Sinwar's brother Mohammed leads the largest Hamas military battalion. Additionally, Mohammed Deif — the elusive Hamas veteran who led its armed wing for two decades and whom Israel claimed it killed in July — was his neighbour, friend, and classmate.