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Short answer
Before you go and blame Israel, blame the Palestinian and the Arab armies that commenced the war of 1948 instead of accepting the state that they were offered by the UN partition plan.
Long answer
In 1948, the Arab-Israeli war, also known as the War of Independence for Israel, began. The war started after local Arabs along with several Arab countries rejected the United Nations Partition Plan for Palestine and attacked the newly declared State of Israel. The primary Arab aggressors were Egypt, Iraq, Jordan, and Syria.