thirds of the workforce had farmed is believed to account for the flight of labourers to work in Israel. As much as 40% of the workforce commuted to Israel on a daily basis finding only poorly paid menial employment. Remittances from labourers earning a wage in Israel were the major factor in Palestinian economic growth during the 1969–73 boom years, but the migration of workers from the territories had a negative impact on local industry by creating an internal labour scarcity in the West Bank and consequent pressure for higher wages there; the contrast between the quality of their lives and Israelis' growing prosperity stoked resentment. Attempting to impose governmental authority, Israel established a licensing system according to which no industrial plant could be built without obtaining a prior Israeli permit. With Military Order No. 393 (14 June 1970), the local commander was given the power and authority to block any construction if, in his evaluation, the building might pose a danger to Israel's security. The overall effect was to obstruct manufacturing development and subordinate any local industrial activity to the exigencies of Israel's economy, or to block the creation of industries that might compete with Israel's. For example, entrepreneurs were denied a permit for a cement factory in Hebron. In order to protect Israeli farmers, melon production was forbidden, imports of grapes and dates were banned, and limits were set to how many cucumbers and tomatoes could be produced. Israeli milk producers exerted pressure on the Ministry for Industry and Trade to stop the establishment of a competitive dairy in Ramallah. The sum effect after two decades was that 15% of all Palestinian firms in the West Bank (and Gaza) employing over eight people, and 32% with seven or less, were prohibited from selling their products in Israel. Israeli protectionist policies thus distorted wider trade relations to the point that, by 1996, 90% of all West Bank imports came from Israel, with consumers paying more than they would for comparable products had they been able to exercise commercial autonomy. Legal status From 1517 to 1917 the West Bank was part of the Ottoman Empire. Turkey, successor state to the Ottoman Empire, renounced its territorial claims in 1923, signing the Treaty of Lausanne, and the area now called the West Bank became an integral part of the British Mandate for Palestine. During the Mandate period Britain had no right of