I understand that some short statements can be a kind of rallying cry to one's friends or an act of defiance against one's foes, and I also understand that many people may be unaware of the arguments for or against a position. That said, if you are dealing with a person or a group of people who are obviously committed to a particular belief, the odds are overwhelmingly strong that they will be aware of any argument against them that is short enough to fit on a bumper sticker, and they probably have spent a good deal of time developing a response to it. If you use your quip with the expectation that it's a magic bullet, you'll just end up looking foolish.
Understand that this applies to all sides of any serious question. I've seen "zingers" deployed against Catholics, against Protestants, against Atheists, against Muslims, against Democrats, against Republicans, against pro-lifers, against abortion supporters, against Capitalism, against Socialism, ... the list just goes on and on. By all means, take a stand on issues that are important to you, just don't assume you are the first to bring up an important point, or that your challenges are unanswerable.