Why though? You should ask why they have not had an independent state in all that time?
They overthrew the Ottoman Empire with help from the British with the understanding that they would be allies with the British. Instead Britain invaded and occupied the country, partitioning it up for sale and accidentally double sold it. Then realized they are super anti-semetic and if they created a zionist colony, they could encourage the Jewish population in England to move there. They chose Palestine and began forcibly creating settlements there. When the Palestinians resisted, they decided it was a bit more effort than they liked and WW2 just happened a few years before, so they gave it over to the newly formed UN. The UN thought this was a great solution to no one wanting their Jewish population anyway and they greenlit, with plausibly deniable language, the joint British and Zionist settler efforts to kill or displace all the Palestinians necessary to create two states: Mandate Palestine and the brand spanking new religious ethno-state Israel. Of course the UN condemned that act of ethnic cleansing later, when it was already done.
