The Yom Kippur War
On Yom Kippur, the holiest day of the year for Jews, in October 1973, Syrian and Egyptian forces, assisted by other Arab nations, launched a surprise attack on Israel. On this specific day (unlike any other holiday) Israel comes to a complete standstill. On Yom Kippur most Jews fast, abstain from any use of fire, electricity, engines, cars, communications, etc. Many soldiers leave military facilities for home during the holiday and Israel is most vulnerable, especially with most of the army demobilized.
Although placed on the defensive for the first two days, Israel eventually was able to counter-attack and repulse the Arab invaders. By the second week of the war, the Syrians had been pushed entirely out of the Golan Heights. In the Sinai to the south, the Israelis had struck at the "hinge" between two invading Egyptian armies, crossed the Suez, and cut off an entire Egyptian army just as a United Nations cease-fire came into effect. An internationally-brokered cease-fire was established after three weeks of fighting. A total of 2,688 Israeli soldiers died in the fighting.