Final answer:
Machiavelli discusses the tactics of Sparta and Rome in holding cities, emphasizing the necessity of ruining cities to retain control.
Explanation:
Machiavelli's secondary purpose in the passage from 'The Prince' was to inform readers about the tactics Sparta and Rome used to hold cities and their effectiveness.
- The description of how Sparta held Greece illustrates the approach of making a city free while permitting its laws, yet failing to retain control.
- The explanation of why Rome dismantled Greek cities highlights the necessity of ruining cities to retain them and prevent rebellion.
- The characterization of liberty as a 'watchword' of rebellion emphasizes the challenge faced when ruling over cities accustomed to freedom.
Learn more about Machiavelli's tactics in 'The Prince' here:
https://brainly.com/question/33841919