1. To regain lost territories from the 1967 Six-Day War. Egypt and Syria had both lost significant territories to Israel in that war, including the Sinai Peninsula, the Gaza Strip, and the West Bank.
2. To alter the balance of power in the region. The Arab states were concerned about Israel's growing military strength, as well as its alliance with the United States. By attacking Israel, they hoped to improve their own negotiating positions and limit Israel's ability to act unilaterally in the region.
3. To unite the Arab world. The Arab world had been divided in the aftermath of the Six-Day War, with some countries, such as Egypt and Syria, adopting a more confrontational stance towards Israel, while others, such as Jordan and Saudi Arabia, favored a more moderate approach. The attack on Israel was seen as an opportunity to bridge these differences and present a united front against Israel.
4. To exploit the element of surprise. The Yom Kippur attack was launched on the holiest day of the Jewish calendar, when most Israelis were fasting and attending synagogue. This gave the Arab states an initial advantage, as they were able to catch the Israeli military off-guard.
The Yom Kippur War ended in a stalemate, with both sides claiming victory. However, the war had a significant impact on the region, and it laid the groundwork for future peace negotiations between Israel and its Arab neighbors.