Balfour had no business carving up land and giving it to one set of people however an inconvenient truth it is for people that there were people living in Palestine.
Israel was created by ethnically cleansing the indigenous population. It suited the wests geopolitical interests. And it supported Zionist ambitions.
Doesn't matter what their origins are, you don't go to your neighbours and say you can't live here anymore.
Zionists even collaborated with the Nazis. - Theodore Herzl stated that the anti semites were allies in achieving his goals.
Ben Gurion's response to the possibility of thousands of Jewish children being admitted into Britain after Kristallnacht was:
"If I knew it would be possible to save all the children in Germany by bringing them over to England, and only half of them by transporting them to Eretz Yisrael, then I would opt for the second alternative. For we must weigh not only the life of those children, but also the history of the people of Israel."
Zionists purchased land in Palestine and put in place policies such as Histadrut - Jewish labour only. Those who employed local labourers were picketed, and often violently, to drive them out.
Their Haganah militants also played a part.
Absolutely Jews must live in peace and safety, it doesn't mean Zionists can ethnically cleanse to achieve that.
Source: The Blood Never Dried - a people's history of the British empire by John Newsinger.
Other examples, Article 7 of the Mandate provided for a nationality law to facilitate the acquisition of Palestinian citizenship by Jewish immigrants, irrespective of origin. This same law denied nationality to Palestinians who were abroad when the British took over.
More sources and also worth reading - mostly by Jewish authors:
Ten Myths about Israel by Ilan Pappe.
100 years of war on Palestine by Rashid Khalidi.
Genocide Bad by Sim Kern
Memoirs of an Arab Jew by Avi Shlaim