Final answer:
The Payne-Aldrich Tariff represented a return to high protective tariffs and signified President Taft's departure from his campaign promise to lower tariffs, much to the disappointment of progressives and southern Democrats.
Step-by-step explanation:
The Payne-Aldrich Tariff marked the return to the old Republican policy of high protective tariffs. President Taft had initially campaigned on the promise of lowering tariffs, a stance that appealed to progressives who believed high tariffs mainly benefited businesses at the expense of consumers.
However, once in office, Taft signed the Payne-Aldrich Act of 1909, which was passed by a conservative-dominated Senate and actually increased tariff rates on many products.
This act betrayed the progressive agenda and solidified the Republican party's return to high protective tariffs, leading to frustration among those who had hoped for reform. The Payne-Aldrich Tariff was a setback for southern Democrats and western interests, as it raised consumer prices for manufactured goods and caused foreign markets to retaliate with their own tariffs on American exports like cotton and tobacco, thereby affecting American agriculture.