The United States didn’t have a working relationship with China because of Corona
By this, he meant that the period was glittering on the surface but corrupt underneath.
The attack affected the american security policies because after the attack the american security system was looked down on and also it was taken care of by making the security more stricter.It impacted the view of Islam because it was done by a Muslim group so Islam was looked at like a religion which allowed killing and brutal acts toward humanity.
I hope this helps and answered the second question based on how I think it is because I am a Muslim myself.