In mid-2019, Israel’s military used a precision strike on a narrow street to kill a Hamas commander whom it called Iran’s money man in Gaza.

The commander ran an off-the-books system of remittances in which trusted agents shuttled physical cash and goods across borders to settle customers’ balances. This so-called hawala network, as it is known in the Middle East, funneled tens of millions of dollars in financing from Iran to Hamas’s military wing.