"God Bless America" has been associated with liberal causes and the expansion of American civil rights throughout its history, as Berlin himself believed in. As a youngster, his family had fled religious persecution in Tsarist Russia.
Beginning in the 1990s, the song has become increasingly and inappropriately associated with Christian conservatives and Tea Party members who have no idea what the song celebrates.
It is important to remember that this song was written by a man fleeing persecution, and is intended as a musical honorarium to the freedoms he found in the United States. Many among America's Right Wing have shown that they will steal, co-opt and pervert anything, including your freedoms as an American (though not their own) , in order to pursue their bizarre social agenda, cloaking the worst anti-Americanism in the Stars and Stripes.
May Kate Smith sit on them . . . and may God bless America!