This belief didn't begin to substantially change until the early 20th century — a handful of years that would become known as the Progressive era.

这种观点直到 20 世纪初才开始发生实质性的变化——那几年被称为“进步时代”。

The author supplements this analysis with an examination of historical trends in conservative thought, such as the forgotten Western agrarian populists of the original Progressive era more than a century ago.

作者通过考察保守思想的历史趋势来补充这一分析，例如一个多世纪前被遗忘的原始进步时代的西方农业民粹主义者。