You are reversing the historical order of these events. The Arabs declared war first, the day after Israel declared independence, and then the Israelis began defending themselves.
It is an extremely well documented historical fact that the Arabs (with considerable encouragement, arms, military support and pressure from the British) began this war, with the clear intent of murdering all of the Jews in Israel.
If your going to turn up and put out nationalist propaganda as truth then you're going to be troll rated straight away. Life should consist in at least fifty percent pure waste of time, and the rest doing what you please.
March 10: Plan Dalet, the plan to ethnically cleanse the Palestinian Arabs, agreed upon by Ben Gurion in the infamous Red House in Tel Aviv.
April 15: Deir Yassin massacre; other massacres recorded before and after. Over 250,000 Palestinians stream over the borders of several Arab countries as refugees seeking safety and asylum. Over 10,000 Palestinian civilians killed in the process including the massacres.
May 15: Israel declares independence.
Now can you give us the date of the start of the 1948 war, when Israel was attacked by neighboring countries? And can you tell us why they attacked Israel?
So why did the neighboring Arab countries invade? Answer this question: why did the US bomb Serbia after the Korsova ethnic cleansing? You will now be able to respond to the former question.