Final answer:
Terrorist groups like al-Qaeda in the Lands of the Islamic Maghreb and the Irgun were formed as part of wider nationalist or extremist movements, al-Qaeda being linked to the September 11th attacks and the Irgun to bombings in 1946. These groups are motivated by a mix of nationalism, religion, and ideology and have evolved to use both traditional and modern tactics for recruitment and attacks.
Step-by-step explanation:
When investigating what group of terrorists did this and when were they formed, it is important to consider the context provided. For instance, the Islamic extremist group al-Qaeda in the Lands of the Islamic Maghreb, which was mentioned as expanding their attacks by the end of the 1990s, is one such group. This group improved its capabilities by joining forces with Osama bin Laden's al-Qaeda. Al-Qaeda is notoriously known for orchestrating the September 11th attacks in 2001, under the leadership of Osama bin Laden, signaling a significant act in the rise of global terrorism.
Another historic example is the Irgun, a more radical terrorist organization, formed during the struggle for Israeli independence and known for its 1946 bombing of the British headquarters at the King David Hotel. Further, the desire for national independence and extremist ideologies are also sources of motivation for various terrorist acts, as seen in the cases of diverse terrorist organizations such as Hamas, Hezbollah, and Boko Haram, with the latter being responsible for 2023 attacks in Cameroon.
It is imperative to understand that terrorist groups have varied in their motivations and objectives, spanning from religious extremism to nationalist ideologies, and they have evolved over time to employ advanced tactics including cyber warfare and social media platforms for recruitment and propaganda.