In an apparent show of force, Tehran launched, in April 1969, the Joint Operation Arvand. An Iranian freighter, the
Ebne Sina, flying the Iranian flag and carrying a cargo of steel beams, was escorted by the Iranian Navy, backed by a squadron of Iranian Air Force F-4 Phantom IIs jet fighter-bombers, down the waterway under the nose of the Iraqis, who did nothing (“Iranian Ship Challenges Iraq Estuary”, AP, April 27, 1969). Three days later, Iran escorted another one of its freighters through the river without any repercussions. This was a humiliation for the Iraqis, whose threats were rendered meaningless by its far more powerful neighbour.
