Christian American adults have less tolerance towards Atheists than towards people who belong to a different Christian Sect or a different Faith.
Religious affiliations in America are changing rapidly. Between 1990 and 2001 the proportion of United States citizens without religious affiliations apparently rose from 8% to 14%, while adults believing in Christianity dropped by 1% per year during the same period. Evangelicals are losing 20-30% each generation.  Should this decline continue over a generation, the United States will change dramatically.
This is all good news because secular democracies tend to do better than more religious nations.    Not all those without religious affiliations are Atheists, Agnostics, Freethinkers etc but quite a number are. In particular young people are more frequently without religion. 
As a consequence, a “siege mentality” may be developing among the Christians, leading many to try and deny free speech to those who so persuasively discourage fellow Americans from being Christians. Does the United States Constitution allow this? Prejudice against atheists is increasing, atheists are accused of being shrill, of New atheism if we promote our views the way believers feel free to promote their beliefs. The majority of American Christians realize there are fewer Christian round them and the opinion leaders - those who influence active church goers - are likely to know even more. Fortunately as the proportion of American Christians declines Christians will less be able to cause problems for atheists and other Non-Christians. Young atheists should face steadily reducing trouble from Christian intolerance as the decades progress. 
Young Americans in the 18 to 25 age group are more likely to accept Evolution. Among Americans over 40 the majority believe in creationism. Young Americans are less likely to go to church; the decline in Christianity is happening mainly as each new generation is less inclined to be religious or to believe in God. Some deconversions happen among older people as well though. As the proportion of atheists increases, ordinary people will increasingly get to know atheists and will increasingly see that we are moral. Actively promoting Humanist morality and showing that we are trustworthy human beings may help reduce prejudice.
Some deconversions in the United States and elsewhere happen because atheists show believers their faith is irrational but most happen because people see this for themselves. Adults, even intelligent older children and young teenagers, if they hear or read a non-Christian folk tale, piece of mythology treat it as fiction. When people have been told persuasively from early childhood to believe the bible not all see the similarity between biblical and other mythology but increasing numbers see this. Shrill atheism may increase the rate of deconversion marginally, it certainly makes atheists more confident. Even if New Atheism were to stop (which is unlikely) the steady erosion of Christian faith will continue.
way to go - you are such a good mom
Pretty good article. More research on the development of atheism will be interesting to see. Even christian studies (the Barna Group) concluded that young people do not self-identify a religion as much as you might expect, preferring to be seen as spiritual. I think we as atheists need to not only fight for truth and against theism but we need to create strong community groups. That is an area where christians are strong and i can appreciate the value of the social services and networks they provide, so much so i wouldn't want to be rid of them without replacing them with something equally or more effective.
Christians are going to have to get used to it. They are getting a reputation for being intolerant asses and bigots. If they don't turn that around, they will develop high blood pressure, shingles, and hemorrhoids. I hope.
And herpes. The kind that doesn't go away. Definitely.
hearing things like this give me hope for a better future. thanx. I needed this today. thanx.
The rising number of atheists adds to the christian anger because their cut and dried system leaves them no answers with which to deal with you. Instead tehy whine and bitch, wanting something to be done with the law so they can offer "intelligent design."
I'm sorry. "God did it" does not explain anything.
Even putting aside the increase in (open) atheists, the decline in religious certainty is a good thing -- as seen in fewer people identifying as "absolutely-100%-certain-god-told-them-so True Believers" and more who identify as "spiritual" but not religious.
Our discussion about Peter Boghossian's A Manual for Creating Atheists ("useful even if you aren't anti-theist"), a couple of months ago, is worth revisiting! One of the points that Luara raised:
You make a very good point. Even the trend towards a less fundamentalist, literal interpretation of the Bible theologically is a positive step for society. I have often said that I have no problem with deism, in my opinion we as atheists have bigger fish to fry.
When it gets personal, some parents indeed realize the problems with the "straight and narrow" little boxes -- of how girls and women, and how boys and men, should look and feel and act and live and love -- that a number of religions presume to cram us all into.
A tangent: Tony Porter's TED talk "A Call to Men" describes the "man box" of aggression, dominance, and misogyny that so many of us are socialized with, and challenges boys and men to break free. The "man box" isn't necessarily religious, but a symptom and enabler of a Dominator culture that assigns restrictive roles to women, and to men.
Also speaking of false boxes and binaries:
John Corvino on "LGBTQrstuv: Bisexuality & Transgender"
Thank you Grinning Cat. Appreciate the video