Why do you suppose people all over the world are risking and sacrificing so much to come to the most hated country on earth?

If it's refugees, it's all a matter of location and ease of access to any particular country. If I'm in let's say Iraq, it's much easier to sneak into Europe than say, the United States. If it's legal immigration, whether permanent or temporary (for work or education), then the United States has the highest number of immigrants. It also changes over time, as political climates change, etc.