When Zaher Jabarin ran a Hamas cell in the 1980s, he borrowed money from his mother to buy weapons. He now oversees a financial empire that the United States estimates is worth hundreds of millions of dollars and that finances Hamas operations against Israel. The Wall Street Journal writes this, citing US and Israeli officials who say the 55-year-old militant manages Hamas's financial ties with its main sponsor, Iran, and the way Tehran sends money to the Gaza Strip. A key figure led by Jabarin, who oversees a portfolio of companies that provide annual revenue to Hamas and manages a network of private donors and businessmen who invest for the Islamic group. Jabarin's influence over Hamas's finances is so great that current and former U.S. and Israeli security officials believe he allowed the group to buy weapons and pay fighters to stage the Oct. 7 attacks. “Jabarin played a big role because he manages all of Hamas’s finances outside Gaza,” said Uzi Shaya, a former Israeli security official who called him “the CEO of Hamas.” Jabarin was then standing near Saleh al-Arouri, the Hamas official killed Tuesday in an explosion blamed on Israel. The two helped found Hamas' military wing in the West Bank and were both considered close to Iran. Israel fears that Hamas's financial empire will remain intact even if it destroys the Hamas army in Gaza. And Jabarin defied Western sanctions for years to use financial systems in Saudi Arabia, Lebanon, the United Arab Emirates, Sudan and most recently Turkey to set up companies and transfer money to Gaza, according to recent and former US and Israeli security officials and Palestinian financial officials.