Zealotry implies excessive zeal and can be viewed negatively as blind passion or intolerance. His zealotry blinded him to other people's perspectives.
Pro Tip 2/3
Strong Commitment
Use 'zealotry' to describe someone with extreme commitment to a cause, often going beyond what is considered reasonable. The reformer's zealotry led him to overlook the complexity of the issues.
Pro Tip 3/3
Not Always Positive
While 'zealotry' involves passion, it isn't always positive and often suggests a stubborn or single-minded approach. Her zealotry for the project ignored all criticism.