What does a historian do when he or she points out problems with an argument?

The historian makes a rebuttal / counterclaim

Explanation:

Refutation is finding the error in a general argument and explaining the same through the use of quotations, reasons or evidence.

The refutation is a statement, an affirmation, which has the following logical structure:  

From a Hypothesis (= H) can be inferred Conclusions (= C)

and if these Conclusions are not given (¬C)

then the Hypothesis is not given either (¬H)

- "schenck v. united states, case in which the u.s. supreme court ruled on march 3, 1919, that the freedom of speech protection afforded in the u.s. constitution's first amendment could be restricted if the words spoken or printed represented to society a “clear and present danger.” "

- speech aimed to potentially create danger could be banned.

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