The thread of irony that snakes its way through the volume strikes me as hugely significant and generally under-discussed in most histories of modern music. RT’s century, which begins in the twenties, is marked by this unstable relationship to the Romantic “Truth,” not by specific musical techniques per se. By placing aesthetic distance and cool irony as the true marker of the modernist mentality, RT susses out some of the major questions of music in the last century: what is music’s place in history, what is its relationship to truth, and what role does it play in society? These questions came under radical scrutiny in the twenties.
As a teacher, the issue of irony seems to come up often in discussions with students. Perhaps this is because, for many, irony is essentially the only musical mode they’ve been exposed to in the popular music of their lifetime. (Or at least sincerity that can easily come off as ironic, like Kurt Cobain.) In any case, students are excited to learn that this expressive mode has a history prior to the Sex Pistols. Neoclassicism also helps contextualize the tricky notion that aping the past in the present is more a reflection of today than it is of that imagined, usable past. (This topic links up to contemporary pop all too well.)
To generalize hugely, it seems to me that major epistemological shifts like this count more in the narrative of music history than progressive steps on the teleological scale of technical development. If tonality (and its disillusion) is the primary bellwether for music historiography, who’s to keep us from beginning the “20th century” with Liszt in the mid-19th century, or Wagner, or Mussorgsky? Schoenberg’s early atonal works or Debussy’s non-functional harmonies seem just as arbitrary a demarcation line for musical “modernism.” In fact, tonality is a highly unstable and short-lived value system to begin with; it seems that just as it comes to maturity, composers begin picking at its seams. What RT points out in the “Pathos is Banned” chapter, however, is a wholesale rethinking of what music can and should do (musical ends), not just an examination of structural/technical poiesis (musical means). (I imagine that Cage and the 1950s will be framed as similarly decisive as a point of historical rupture.) This shift, as Mark trenchantly observed, is still active today.