Structure
The arrangement of your answer is impeccable because, in the first paragraph, you explain the meaning of state-sponsored terrorism and passive support for terrorism. In the second paragraph, you talk about the issues that lead to terrorism and the valid reason why people join extremist groups, which is “national resistance cause.”
Thirdly, you talk to analyze why you think passive support of terrorism makes it more difficult for countries like the U.S to come up with counterterrorism measures. I love how you have given the example of 9/11 and how it was influenced by a haven for Al Qaida in Afghanistan.
Lastly, the structure is further made understandable by explaining how terrorist groups find it easy to grow in areas or countries where they receive passive support because they became liberal in taking any action due to massive gained territory.
The structure shows consistency through use of evidence, and the size is generally uniform.
Grammar
The grammar is on the point, but only minor correlation, I think, will help in the discussion being clearer. In the second sentence in the first paragraph, you have used “this” to start a point that might be unclear to the reader on what you are referring to specifically. The use of full stop and commas is nicely done, but I have noticed an issue in your citation where you use a semicolon between the year of publication and the page number, and I think a comma will be the most appropriate. Additionally, you say “it is apparent and easy to see,” which I think is repetition because the name “apparent” means something visible. I would cite properly and avoid repetition, and this would make the discussion flawless. Generally, when it comes to grammar, you have done an impeccable job.
Content
I reasonably agree with you that passive support of terrorism is dangerous because it becomes hard to control the actions of these extremists groups such as Al Qaeda. However, you mentioned that religion is just a tool for national resistance cause, but I think that religion and people who engage, especially in suicide terrorism, play a fundamental role. In the TED Talk, Obaid-Chinoy asks a young boy why he joined terrorism, and his answer was to make God happy (2010, 6:39). This young man’s statement proves that terrorism, especially when it comes to young people, is more embedded in their belief and quest to identify themselves and not necessarily because of a resistance cause. I think distinguishing the difference between the two will be essential in understanding terrorism and what influences suicide bombers.
Overall, I believe that you have satisfactorily tailored an educative discussion that highlights one of the problems facing the world.