Russia is 80% Russian Orthodox... Which means Christian. There are more Christians than the United States has by percentage. And another thing I should address is that they have a Democracy, election for a new president every four years, meaning it's not Communist. Know more about Russia before making assumptions like that.
In our country, we have freedom of religion and while we were founded on Judeo - Christian ethics, we were also founded on equality. While I do not know a lot about Russia, I do know that they do not treat everyone equally. Also, with the changing of times, religion and thoughts of people its assumable that we would change our laws with the change of times.
Seeing that the United States is a secular country (even though a good portion of its citizens affiliate themselves with Christianity) it's of no surprise really and it shouldn't be. According to Eastern Europe Russia and Central Asia document (see below), the majority consensus of Russia affiliate themselves with Orthodox Russian Christianity and that country's government recognizes it as their "historical heritage" so let's look at the situation carefully. Russia identifying itself as a "Christian" nation does ban it based on their religious ideology versus United States who doesn't identify itself as a Christian nation (except for fundies) then it shouldn't come to no surprise that USA chose a secular viewpoint on the matter versus religious. With the statement of the USA to be founded on Christian principles, please see the second link listed below to show how this view is incorrect.
Although Russia is considered a "godless" country, and America is a country considered under "god", America has always supported those to make their own choices and choices without politics intervening. As with Russia it is ruled with an "iron grip" and does not want people to stray from their ideal way life should be by expressing themselves.