In the afterword of "The End of Faith," Sam Harris responds to criticism that "the greatest crimes of the 20th century were perpetrated by atheists...Hitler, Stalin, Mao, Pol Pot, and Kim Jong." Harris answers by saying, "these regimes have been mere litanies of delusion-- about race, economics, national identity..."
Note that all but one of these depots (Hitler) were communist. Almost all atheists whose writings I have read are more than atheists; they are empiricists. That is, they require evidence to establish the probability of truth to a claim. Before an empiricist would accept communism as a valid solution to the world's problems, an empiricist would have to have evidence that communism would work. Although we now have evidence that communism does not work, suppose we could go back in time before the Soviet Union and an empiricist evaluated whether communism would work well. The empiricist would examine the definition of communism:
"Communism is a social structure in which classes are abolished and property is commonly controlled, as well as a political philosophy and social movement that advocates and aims to create such a society.
Karl Marx posited that communism would be the final stage in society, which would be achieved through a proletarian revolution and only possible after a transitional stage develops the productive forces, leading to a superabundance of goods and services." http://en.wikipedia.org/wiki/Communism
An empiricist would need evidence to support the multiple claims of communism; namely that:
1. Abolishing social classes is possible and would result in a better world,
2. Public ownership of all property is fair and would result in a net gain for society, and
3. The only way to do 1 and 2 is by violent revolution.
An empiricist would, first of all, need to be shown how all of this could be done without violating basic human rights. If communism passed that test, s/he would want to see communism work on a small scale (a commune) and then a larger scale (a city or small nation). In my opinion there is no way communism would have passed the tests of an empiricist.
So, if all atheists changed their label to empiricist, atheists would be more accepted as a group because atheists would not be associated with communism. However, we know that atheists are pariahs of society. http://www.religiondispatches.org/dispatches/laurilebo/2783/the_soc...
However, I think that many theists would not realize that an empiricist, by definition, is an atheist. Many Christians would claim that they too are empiricists because they always examine evidence, i.e. The Bible, before they establish the probability of truth to a claim. As such, empiricists would have difficulty in fighting the detrimental effects of religion since there could be no unity of claims. There would just be the pseudo-empiricist theists fighting the de facto atheist empiricists.
As atheists, however, we have no problem with theists trying to hop on board our wagon, so to speak, because theist do not want to be on our wagon. Hence, as atheists (not empiricists) we can better make progress toward fighting the detrimental effects of religion. I suppose it is not realistic to expect the world will understand that atheists are not communist, since we do not have access to pulpits in the churches. About as much as we can expect is that authors such as Dawkins, Harris, Dennett, Hitchens, (and hopefully me one day) will continue to publish books that will educate the populace about atheism.