I've been a bartender for around eight years now on and off. Don't make much in the way of bar-tending, unless you know how to talk to folks. Sometimes a good conversation is the only thing that keeps a customer in their seat on a slow day so keeping abreast the news and current events is important for me.
Some folk have the gift of gab, others need a few drinks to loosen up. Regardless of how loquacious you are there are two things you should never discuss in a bar; religion and politics. I don't know who made this rule but I have an inkling that it was a very wise bartender from days of yore.
'Spirits' and religion just don't mix. Most Churches don't even use wine in communion services anymore and I for one don't want to have a conversation about Jesus, Mohammad, or Buddha while I'm 'tying one on'. More often than not someone is going to be offended and accuse you of 'stepping on their faith' at best or 'heresy' at worst. Don't drink in Church and don't proselytize in a tavern.
The only politics that should be discussed in a bar are the terms and duration of happy hour. Politics is a sour subject, a couple of beers and cocktails turns everyone into an expert. A 'loud 'n' proud' expert who's right about everything. A barstool is not a soapbox and Jim Beam isn't the speaker of the house (or maybe he is...), leave your political colors at the door.
Religion and politics excite strong emotions and stronger opinions. When people consume alcohol whatever they were feeling before they started drinking is amplified. If you're sad you get sadder, if you're angry you get madder and so on. Talk about celebrities, sports, whatever, just respect those around you and leave god and country out of it.