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Keyword difficulty should be based upon the skills of the author and how good of a job that you can do against the content of the competition. If you can beat their content, go after them. Do not fear competition, because where there is competition there is plenty of traffic and plenty of money changing hands.   Even if you do not rank at #1 right away there is still long tail traffic and searchers going onto the second page. The greatest risk that you have by taking the advice above is if you are not honest with yourself about your abilities.  If you go challenge a battleship with a potato gun then even God will not be able to help you.