Machiavelli suggests in Chapter 7 that a prince should always keep his word and be honest in his dealings with others

Actually, your statement is not entirely accurate. In "The Prince", Machiavelli suggests that while it is desirable for a prince to be seen as honest and trustworthy, he should not be afraid to lie or break his word if it is in his best interest to do so. He argues that a prince should strive to be both loved and feared, but if he cannot be both, it is better to be feared than loved. This is because people are generally ungrateful and fickle, and will turn against a ruler who is too kind or trusting. Therefore, a prince should be willing to be deceitful when necessary to maintain his power and protect his state.