Terrorism is taking a huge toll in the modern society, killing innocent people, destroying historical places and disturbing international politics. Elimination of terrorism, therefore, has an utmost importance. However I don't think international terrorism will ever be eliminated for the following three reasons.
Firstly, there is and will be a persistent root cause for terrorism: economic inequality. People in impoverished countries sometimes resort to terrorism as a means of making large sum of money. They usually have a strong sense of animosity toward affluent people in developed countries, and attempt to attack wealthy people.
Secondly, there are some problems with the education system in Africa and Middle Eastern countries. Schools in these countries are often underresourced and understaffed, and thus cannot provide adequate education for young people who are naive and can be easily influenced by propaganda videos circulating SNS. Schools should equip students with enough knowledge about the danger of terrorist activities.
Thirdly, historical background is also stoking conflicts in politically unstable regions. Differences in ideology and religion are usually deep-rooted and difficult to overcome, leading to ceaseless fighting in poorly-governed areas. And fighting shows no sign of ending because of the sad nature of violence: violence provokes more violence.
For the above-mentioned three reasons, the idea of complete elimination of terrorism is far from realistic despite the enormous efforts being exerted by the international communities.
追記： circulatingの後に前置詞必要。differences in ideology and religious beliefsにしたかった。ceaselessは最初incessantにしようと思ったけど綴りがわからなくてceaselessにした。equip students with enough knowledge about the dangerの所にinculcateという語を使おうとも思ったけど自分の下手なライティングに難単語が入ると不自然そうなので断念した。