Should an answer be marked as unhelpful merely because it contains an incorrect statement?

In my opinion, no. That is the reason that we have the "Refute Fact" capability in the Answers system. You can correct incorrect statements and get a point for doing it rather that voting unhelpful.

However, if an answer provides a technically correct but dangerous answer, then I think you should use the unhelpful vote. In addition, I think you should be required to leave a comment when giving an unhelpful vote. The answerer may never know why the got an unhelpful vote if the voter doesn't leave a comment.

That's a judgment call. It depends on the impact of the incorrect statement on the level of helpfulness of the answer. For example, if a question asks where the asker can find Bed Bath and Beyond coupons and the answer sends the asker to Wikipedia, I'd say that is an unhelpful answer.

However, if a question asks e.g. For help in identifying possible tax deductions, and the answer provides a great deal of useful information and links, and mistakenly states that the agency in charge of taxes is INS (the old abbreviation of the USCIS when it was still called the Immigrations and Naturalization Service) rather than the correct IRS for Internal Revenue Service, then in that case I would not say the answer is unhelpful. In this latter case, I might post a comment saying that the answer is good, but would then provide the correction needed. Some members draw the line far more aggressively than I do, perhaps feeling that any wrong information in an answer makes it unhelpful - sort of "perfect or no good".

Others even vote an answer as unhelpful in cases where they simply do not agree with an opinion, which might be a legitimate one. That use of the voting power is frowned upon and discouraged on Mahalo.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.