There is some discussion on Christian CADRE on whether atheists are closed-minded and angry. Here is my response:
I have sometimes wished that atheists had some sort of authoritative statement in their writings equivalent to I Pet 3:15, which says "Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have. But do this with gentleness and respect."
We've all seen people on the internet with Angry Atheist Syndrome, who can't find any room in their minds to acknowledge any point made by Christians, however legitimate it might be. Some people abandon their faith and then go on a crusade against what they once believed in. But that is by no means universal. Blue Devil Knight, a staunch atheist, has a reputation for fair-mindedness on Dangerous Idea. On the other hand, Christians fight dirty, sometimes, too.
All of us get angry from time to time, myself included. I think some people feel angry and betrayed if they were Christians once and then found it all unbelievable. I think the "delusion" rhetoric is also partially to blame.