Answer:
The answer to this question is difficult and there are many factors that must be taken into account, in order to pinpoint three specific factors. There have been military and political conflicts that led to a rise in terrorism in the 21st century, but these are specific to terrorism from and in the Middle East, like are the Invasion of Afghanistan, the War on Terror with the Invasion of Iraq after 9/11, and the rise to power of radical terrorist regimes like the Taliban, among others. However, I would say that the three leading factors that have led to a rise in terrorism worldwide, and not just from and in the Middle East, would be:
1. Religious hatred: Fanaticism and radicalism in religious beliefs, as well as the intolerance towards religious differences has led to an increment in world-wide terrorism.
2. Political differences and intolerance: Especially in countries like those in Africa, and also in the Middle East, this factor has shown how political intolerance leads to further terrorism, as people seek to fight that which is different, and especially when they are outpowered, through terror attacks and strategies. An example is the massacres that have taken place in Africa between leading groups and those out of power.
3. Corruption: Corruption and poverty are also factors because they have fed fanatical viewpoints and actions. In the desire to fight off fanatical regimes, and corrupted governments, both nationally and internationally, people have resorted to terror, especially to fight off powerful regimes, and nations.
At the turn of the 21st century, all these factors generated a chain reaction that led to such events as the 9/11 attacks, and others around the world.
