According to this thread, the Prince is is NOT satire https://www.reddit.com/r/AskHistorians/comments/2wc8ou/what_was_the_actual_impact_of_machiavellis_the/?ref=search_posts

Hi, you may be interested in this post from the FAQ

• Why did Enlightenment philosophers try so hard to "redeem" Machiavelli's The Prince as republican satire? Were they right? - featuring /u/CogitoErgoDoom, /u/Tiako and others