Israel accepted the 1947 UN partition resolution; the Arabs rejected it. Immediately Israel declared independence in 1948, the Arab League declared "Holy War", with the publicly announced intention of driving the Jews into the sea. Lebanon, Jordan, Syria, Egypt and Iraq invaded the newborn state, expecting to destroy it in a matter of weeks. Arab League Secretary, General Azzam Pasha declared "This will be a war of extermination and a momentous massacre which will be spoken of like the Mongolian massacres and the Crusades". The Mufti of Jerusalem, Haj Amin Al Husseini pronounced "I declare a holy war, my Moslem brothers! Murder the Jews! Murder them all!"
To really understand what 242 is about, who better to turn to than one of the authors of the resolution, the late Eugene Rostow. In an article "Are the settlements legal?" in The New Republic, (October 21, 1991), Rostow wrote:
"Resolution 242, which as undersecretary of state for political affairs between 1966 and 1969 I helped produce, calls on the parties to make peace and allows Israel to administer the territories it occupied in 1967 until "a just and lasting peace in the Middle East" is achieved. When such a peace is made, Israel is required to withdraw its armed forces "from territories" it occupied during the Six-Day War--not from "the" territories nor from "all" the territories, but from some of the territories, which included the Sinai Desert, the West Bank, the Golan Heights, East Jerusalem, and the Gaza Strip.
Five-and-a-half months of vehement public diplomacy in 1967 made it perfectly clear what the missing definite article in Resolution 242 means. Ingeniously drafted resolutions calling for withdrawals from "all" the territories were defeated in the Security Council and the General Assembly. Speaker after speaker made it explicit that Israel was not to be forced back to the "fragile" and "vulnerable" Armistice Demarcation Lines, but should retire once peace was made to what Resolution 242 called "secure and recognized" boundaries, agreed to by the parties. In negotiating such agreements, the parties should take into account, among other factors, security considerations, access to the international waterways of the region, and, of course, their respective legal claims."
The indisputable facts are that prior to 1967, the West Bank and East Jerusalem were not possessed by the Palestinians but were ILLEGALLY occupied by Jordan. Gaza was similarly, ILLEGALLY occupied by Egypt, both countries having illegally invaded the territories in defiance of the 1947 UN Partition Plan. Jordan resolved to annex the West Bank and Jerusalem in 1950 but this attempt at annexation was rejected by the vast majority of the international community, including the Arab states. Only Great Britain and Pakistan recognized this attempt at annexation.
It is relevant to quote former State Department Legal Advisor Stephen Schwebel, who at one time headed the ICJ. In 1970 he wrote: "Where the prior holder of territory had seized that territory unlawfully, the state which subsequently takes that territory in the lawful exercise of self-defense has, against that prior holder, better title. It is a matter of history that Israel only entered the West Bank in self-defense. It is also a matter of record that the UN rejected Soviet efforts to have Israel branded as the aggressor in the Six-Day War".
...Israel's presence in the West Bank and Gaza may be justifiable or unjustifiable, wise or unwise, but it certainly is not illegal until such time as a just and lasting peace is achieved.