Who declared war on whom — 1948
Upon the expiration of the British Mandate on May 14, 1948, Israel declared independence — a legal succession of a recognised territorial unit. The following day, the armies of Egypt, Transjordan, Syria, Iraq, and Lebanon initiated military hostilities. The sequence is unambiguous and documented.
Pre-state violence follows the same pattern: organised Arab attacks on Jewish communities predated Israeli statehood throughout the 1940s. The conflict did not begin with Israeli military action. It began with the Arab rejection of partition and the decision to resolve by force what could have been resolved by negotiation.
The foundational cause-and-effect is this: Israel was offered a state, accepted it, and was immediately attacked by five Arab armies. The Arab side was offered a state, rejected it, launched a war to destroy the other side's state, and lost. Every subsequent territorial and legal question flows from that sequence.
The stated objectives of Arab leadership at the time leave no ambiguity about the nature of the war: