In 1948 zionist forces did not simply defend the areas the UN allocated to a Jewish state, they invaded the parts allocated to an Arab state.
While Iraq and Jordan defended the future West Bank, in the south Egypt could hold only the Gaza Strip.
In the north Lebanon and Syria did not hang on to an inch of Galilee.
As a result Israel used the cover of war to drive out thousands of Palestinians.
As for 1967, Israel's principal aim was to take out Egypt - something it failed to do in 1956.
First it provoked Syria through incursions along the 1949 Israel-Syria armistice line.
Egypt came to its ally's aid. Israel's strike only arose from a crisis Israel provoked. This led to Israel occupying the rest of Palestine.