I think I was at school and had only noticed it on the television when I arrived at home. It didn't affect me that much since I didn't lose anyone and I was still a child, so I had no real concrete concept of despair just yet. The text below is purely logical and factual and not in the least meant to be heartfelt, so don't read if you're overly sensitive to the actual events of 9/11.
Although the events of 9/11 were undeniably horrible, forgive me for saying that from a national security standpoint they were, for lack of a better word, necessary. I don't mean any disrespect to those lost or to those who have lost; the event could have been any terrorist attack on par with the 9/11 attacks, but the events did increase the standards for travel security measures and national security measures. Although many new security measures seem like a hassle and are widely perceived as unnecessary or inappropriate, it's comforting to know that thousands of terrorist ploys have been halted annually ever since that day. With the old laws and standards, an attack of 9/11's scale was bound to happen; governments and privatized businesses never viewed security as a big factor before then, and lord knows the population didn't either because most people have a "it could never happen to me" mindset. Many people still think of departments like Homeland Security as violent and cruel, as well, but, more often than not, the work done is extremely effective, and the system is very rarely slipping up. We also have to take into account the creation of departments such as the Transportation Security Administration, as well, which is doing a fine job of keeping our travel lines safe. The point is that before 9/11 our travel lines and laws were far too lenient, and an event on such a scale will not be seen for quite a long time (at least in major cities and locations, obviously omitting areas such as Darfur) thanks to a well-learned and implemented lesson.