By Nidal al-Mughrabi
GAZA, Nov 14 (Reuters) - Ahmed Al-Jaabari, the Hamas military chief assassinated by Israel in the Gaza Strip on Wednesday, knew his days were numbered from the moment that he agreed to free Israeli soldier Gilad Shalit, the hostage whose capture he organised.
"Jaabari was living like a martyr in absentia, a martyr in waiting," an aide to the late commander told Reuters.
The Israeli domestic intelligence organisation Shin Bet said Jaabari, who had already survived an air strike in 2004, was the mastermind of the cross-border raid launched from the coastal strip that captured the Israeli corporal in 2006.
Five years later, he helped to negotiate the release of Shalit in exchange for 1,047 Palestinians held in Israeli jails, earning praise in Gaza and, in his view, a death sentence from Israel.
"He spoke about martyrdom all the time, but he felt the Israelis would wait until the conclusion of the Shalit deal," said the confidant, who declined to give his name.
Israeli officials say Jaabari was involved in financing and directing attacks against Israel, and Israeli President Shimon Peres called him a "mass-murderer" in a call to U.S. President Barack Obama.
Jaabari, 52, was held in an Israeli jail from 1982 to 1995 for terrorist activity on behalf of Yasser Arafat's Fatah movement, before switching allegiance to Hamas.
Jaabari was formally the deputy to Hamas's chief commander Mohammed Deif, but in recent years he had effectively become chief of staff of the Izz el-Deen Al-Qassam Brigades, Hamas's armed wing, after Deif was badly wounded in an Israeli attack.
He had already been wounded in an Israeli air strike on his house in 2004 in which six people including his son were killed, and he maintained a very low public profile.
Hamas rejects Israel's right to exist and says it aims to create an Islamic state in all of Gaza, the West Bank and Israel.
"Jihad and resistance are the only ways to liberate the homeland, and not negotiation and bargains," Jaabari said in an interview with Reuters in September 2005.
"We will continue regardless of the cost, and at the end God will offer us victory."
Assassination of top Palestinian militants has long been part of Israel's security strategy. Wednesday's strike confirmed that Israel is prepared to resume the tactic, which Hamas and other armed factions say leave them no option but to retaliate, adding to the cycle of violence.
Israel Defence Forces spokeswoman Colonel Avital Leibovitch said Jaabari's killing was the first attack in an "operation against terror targets, Hamas, Islamic Jihad and other terror groups".
Hamas founders Ahmed Yassin and Abdul Aziz Rantissi were both killed in Israeli air strikes in 2004. (Writing by Noah Browning; Editing by Kevin Liffey)