Inaugural addresses are usually more about tone than detail. However, in his second inaugural, President Obama casually and successfully presented both at once. This kind of rhetorical effort is especially effective for speeches about controversial initiatives; the comforting suggestion to the audience is that the unfamiliar is of a piece with what we already know—that everything new is old again. President Obama presented controversial ideas as merely a fresh tactic toward an old strategy.
He has good reason to believe this approach will work. When supporters hear new ideas set alongside unquestioned pillars of culture, as they did in this speech, they imagine those new ideas less as experiment and more as writ.
Casual listeners simply hear traditional language and assume that anything mixed in with it is also traditional, or at least widely accepted. The only people who would be put off by the content of this speech would be highly engaged listeners who are never going to agree with the speaker anyway.