Trump was not wrong...Palestine has existed since 1948...Even longer...
Of course, there has NEVER been a nation known as Palestine...Only a region, but it was in existence in 1948.
The history of a distinct Palestinian national identity is a disputed issue amongst scholars.[36][37] Legal historian Assaf Likhovski states that the prevailing view is that Palestinian identity originated in the early decades of the 20th century.[36] “Palestinian” was used to refer to the nationalist concept of a Palestinian people by the Arabs of Palestine in a limited way until World War I.
Well, actually the Roman empire about one hundred years after Christ expelled the Jews and renamed the area Palestine to remove the ancient claim of the Jews upon their homeland. There actually was no Palestinian nation.