In what way did the McMahon-Hussein Correspondence and the Balfour Declaration contribute to escalating the Israel-Palestine conflict?

Until 1918 the region of Palestine or today's Israel belonged to the Ottoman Empire. As the declining empire joined the Central-Powers, the war also spread to Palestine. To secure the win over the Ottomans, the British closed a deal in 1915 with Sherif Hussein of Mecca. This agreement is also known as the McMahon-Hussein Correspondence and includes the promise of an independent Arab State, including Palestine in return for the military help of the Arab tribes against the Ottoman Empire. Two years later the British Government was again involved in a significant trade deal: The Balfour Declaration. To receive new resources and strategic Advantages, the British agreed on the Zionist aim of founding a Jewish homeland in Palestine and gave the Zionist movement a guarantee for these lands.  With their seesaw policy the British, who were now in charge of Palestine created a conflict between the  Arab and Jewish Population as both sides claimed the land as theirs referring to the agreements. As more and more Jewish settlers arrived in Palestine, also the conflict grew more violent. The foundation of Israel in 1948 shifted the whole problem to a new level, as the Arabs now felt betrayed and robbed of their homeland. This feeling of betrayal is still in the mind of many Palestinians and significantly contributes to the conflict between Arab-Palestinians and Israelis.