· What is terrorism, how many terrorist attacks occur annually and is it only a recent problem? Find out in our analysis of terroristic acts and groups. · This chart shows the estimated financial and human costs of the U.S. 'War on Terror' since the 9/11 attacks. · Lockerbie in 1988 marked the worst terrorist attack in UK history, claiming the lives of 270 people. · Nigeria has one of the highest terrorism threat levels in the world. Despite a general decrease in terror-related deaths, the country recently recorded the eight highest … · This chart shows the impact of terrorism according to the Global Guardian Terror Index 2026. The American Civil War is the conflict with the largest number of American military fatalities in history. Find the most relevant statistics on terrorism in Europe · In 2023, Syria was the country with the highest number of terrorist attacks, reaching 1,405. That year, more than 7,382 terrorist attacks were registered worldwide, …