〜について and 〜に対して: topic and target
Compare について for the subject matter of speech or research with に対して for the target of an action or attitude. Use each phrase's role in the sentence rather than relying on a similar translation.
Identify the subject being discussed
江戸時代の暮らしについて調べています。 means that someone is researching life in the Edo period. Place the subject matter of speaking, writing, or research before について.
これは海の生き物についての本です。 uses についての before a noun. It describes the book as one whose subject is marine life.
Identify the target of an action or attitude
市役所は住民の提案に対して、来週回答します。 says that city hall will respond to a resident's proposal next week. The proposal is the target of the response.
子どもに対して優しい言葉で話してください。 focuses on the manner in which someone addresses children. The person or thing toward which an action or attitude is directed comes before に対して.
Choose by role even with related nouns
新しい規則について意見を述べました。 means that someone expressed an opinion about the new rule. The rule is the content being discussed, so について fits.
その意見に対して、参加者から質問が出ました。 means that a question came from a participant in response to the opinion. The opinion is now the target of a reaction, so に対して fits.
Quick check: To say that you wrote a report about history, is 歴史についてレポートを書きました more natural than 歴史に対してレポートを書きました?
Show the answer and why
Yes. History is the subject matter covered by the report, so について is natural.