Kenneth G. Wilson (1923–). The Columbia Guide to Standard American English. 1993.
protect (v.)
when it combines with prepositions, usually does so with from or against: Protect yourself against [from] the flu by getting a flu shot. By and with also occur, indicating the protection itself rather than the thing to be protected against: She protected herself by taking her German shepherd with her on her evening walks. The mansion was protected with elaborate electronic warning devices.
