In any case, as I've said beforee, if the argument is "we're reclaiming land that was wrongfully taken from us", that's fine, we can discuss that issue - however that's very different from the gist of this article which is basically saying that Palestine was vacant, unclaimed and freely available for Jewish settlement.
The formal start of Zionist immigration to Palestine is usually given as 1880 or 1881, but people on this planet are always moving around. The "Balfour Declaration" was just as irrelevant as comparable promises given to Arabs. The British did not hand over Palestine to the Jews. They came closer to handing it over to the Arabs. Israel was won in battle, just like the United States and just about every other place on earth was won. After World War II, the Arabs, freed of Turkish and British colonialism, tried to kick out the Jews from newly established states. In Israel, unlike Syria, or Egypt, or Yemen, or Iraq, the Jews who fought back won one small sliver of the Middle East for a tiny mostly Jewish state. All the British and United Nations resolutions had just about zero influence on this.