Tzur also prepared the IDF for a war with the Arab armies and built up the defense forces so that it could stop Arab attacks. In August 1961, the president of Egypt, Gamal Abdul Nasser, revealed that Israel had obtained Dassault Mirage III jet fighters in order to counter Egyptian Soviet-made MiG-19s. The Mirages proven themselves very well and served as the Israeli Air Force's main fighter for many years. The Mirages contributed substantially to Israel's victory in the Six-Day War and the elimination of the combined Arab airpower of Egypt, Syria and Jordan, as did other two notable acquisitions by Tzur, the Centurion tanks and MIM-23 Hawk surface-to-air missile technology.