You are aware that 100's of thousand of German Jews seeking to immigrate to the Palestinian Mandate as well as countries like the US and Canada were turned down, aren't you?
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The British did not want to get stuck with the problems that they thought this would have created.
This happened in the 1930's during a worldwide Depression. A lot of people at that time actually thought that there was a "Jewish Problem". The WWI Peace Treaty tried to give every nationality a homeland, but some people, like the Jews and the Gypsies, were left out. Jews were generally disliked and considered to be a nuisance in many countries.
Hitler would have preferred a Judenfrei world to a Judenfrei Germany, but in the beginning, he seemed to favor the latter: it is less bloodthirsty. He was not what anyone could call an honorable man. I think most people agree on this now.
