I still want to be able to say Merry Christmas without getting an awkward look. I don't say "Happy Holiday" on Easter or Halloween, why should I have to change my greeting for Christmas? If someone says they're Jewish, I'd wish them a Happy Hanukkah. If someone says they're an Atheist, I'd say Happy December 25th. Same if someone says they celebrate the Kwanza feast, I'd say (you guessed it) Happy Kwanza.
But I think the main reason it appears that Liberals are "afraid" of religious politics in power is the very shady, and rife with murderous acts, history such power has. This "war on terror" could very well be looked at as an extension of religious political power campaigns of the past. (<Unintentional aliterative tongue twister
) "We are with Israel, you are against Israel, we are against you" seems to be a big part of deciding who the US puts in the Axis of Evil.