On May 14, 1948, the British Mandate officially expired. That same day, the Jewish National Council issued the Declaration of the Establishment of the State of Israel. About 10 minutes later, President Truman officially recognized the State of Israel, and the Soviet Union also quickly recognized Israel. However, the Palestinians and the Arab League did not recognize the new state, and the very next day, armies from Egypt, Syria, Lebanon and Iraq invaded the former British Mandate to squelch Israel, while Saudi Arabia assisted the Arab armies. Jordan would also get involved in the war, fighting the Israelis around Jerusalem. The eventual armistice lines became known as the "Green Line," and the conflict has continued to involve those lines and the issues that were contested in a war now nearly 70 years old.

In early June 1967, the Israelis captured Jordanian intelligence that indicated an invasion was imminent and thus launched preemptive strikes. Over the next six days, the Israelis overwhelmed the Egyptians in the west, destroying thousands of tanks and capturing the Gaza Strip and the entire Sinai Peninsula. At the same time, Israel drove the Jordanians out of Jerusalem and the West Bank, and it captured the Golan Heights from Syria near the border of Lebanon. In the span of a week, Israel had tripled the size of the lands it controlled. Israel had gone from less than 10 miles wide in some spots to over 200 miles wide from the Sinai Peninsula to the West Bank. Israel also unified Jerusalem.

On October 6, 1973, Syria and Egypt caught Israel off guard during the Jewish holy holiday of Yom Kippur, surprise attacking the Sinai Peninsula and Golan Heights. The Israelis turned the tide within a week, going on the counteroffensive and winning the war within 3 weeks.