Retired intelligence officer Peter Oleson wrote this short review in the Winter-Spring 2023 issue of The Intelligencer: Journal of US Intelligence Studies:
The 2021 volume is the twentieth in a series documenting terrorism, which Mickolus defines as “the use or threat of use of violence by any individual or group for political purposes.” He overviews regional developments, the activities of key terrorist groups, and the fates of significant terror figures – who was killed and who was captured. This precedes a chronology of terrorist events by continent, country, and date. Mickolus includes domestic terrorism events within the United States, including a lengthy section on the January 6th events at the Capitol. Terrorist Events Worldwide is a good example of open source exploitation. The series is a good starting point for any research on terrorist events.
PDF of review in The Intelligencer: