23. But it's not as if earlier times didn't know perpetual war, disaster and the massacre of innocents.

【分析】复合句。主句是主系表结构，as if引导表语从句。在表语从句中，主语是earlier times,隐含的是the people in earlier times;谓语是didn’t know;宾语是三个并列的名词及名词短语。
【译文】但这不是说以前的时代没有经历过连续不断的战争、灾难和滥杀无辜。

24. The rise of anti-happy art almost exactly tracks the emergence of mass media, and with it, a commercial culture in which happiness is not just an ideal but an ideology.

【分析】简单句。句子主干为The rise of anti-happy art ... tracks the emergence of mass media and ... a commercial culture。with it 中 it 指代 the emergence of mass media。which引导的定语从句修饰先行词a commercial culture,其中使用了 not…but…结构。
【译文】反快乐艺术的兴起几乎完全可以追溯到大众传媒的出现，以及随之兴起的商业文化,在这种文化中，快乐不仅仅是一个理想，而且是一种意识形态。