I think that is the part that's the deal-breaker for me. I hate to be this guy, but chances are that none of these issues do or will ever reach a circle where you are affected, and the reverse is also true. Most people will never be in the same city as a mass shooting. Even less will ever perpetrate one. Most people aren't denying gays service or calling for mass deportations. The problem is that we find the special snowflake who is pulling these stunts and we make a huge deal about it. We all throw our handful of pine needles onto the fire, and watch it turn into a consuming inferno.
This has two effects. The first is keeping the wrong thing in the spotlight. Some people are dicks. it happens. There's probably a kid from your high school who spent most of the class trying to anger his teacher or fellow students. You probably don't remember his name. The question is why do we keep putting the camera on people we don't like? Why do we let these people be spokesmen for causes with a 1% approval rating? People lose their pedestals as soon as there is no longer a camera pointed at them. So stop supporting them.
The other effect is that it that original thought and solid argument break down. When I was in debate, almost the first thing I learned was to never combat an argument by saying it is ridiculous. Even if that is perfectly true, it conditions debaters to stop thinking about issues on the simple but incorrect notion that the fault is manifest. There are truly crazy theories promoted all over the world. Usually these come out of a basement that reeks of BO and stale Doritos. As you might expect, these sorts of people don't get very much street cred or any other type of cred.
On the other hand, there are those with a much larger circle of influence. This is usually because their argument, although the final point is bogus, it stems from some valid arguments or builds on something more intangible, like fear or anger. When 90% of people recognize that the argument is ridiculous, usually Facebook fills up with denunciations filled with ad hominem attacks and usually concludes with such statements as "only someone crazy would believe this."
One of the most poignant messages I learned on my mission was that the best way to ruin a perfectly good argument is to represent it poorly. This is why I refrain from ever commenting on such issues during the heat of the moment. Nobody is interested in listening or debating. The foremost issue on everyone's agenda is to make sure it's clear that everyone knows that they're not one of those idiots who supports the opposition. The arguments aren't arguments at all. They're propaganda. Propaganda in a positive direction? Perhaps. However, it turns the internet into a giant echo chamber.
I mentioned that I felt this same problem brewing in the mission. There, I was always in an apartment with three other guys who were currently spending their lives in the exact same way I was. Perhaps 75% of the time, one of the guys was from Utah or southern Idaho. Back in the MTC, a speaker chuckled about a missionary who said that he couldn't work with Elders from Utah. I didn't laugh. Although I have nothing against Utah natives, there is a definite effect of being immersed in a culture where they are the majority. I grew up in Washington, and I spent three years on a debate team filled mostly with individuals with very opinionated, opposing views. I was a minority in this respect, and the collision of ideals ultimately did much more help than harm.
I am profoundly thankful for my parents, who taught me that the majority of people are good people, and usually their beliefs, once dissected, are completely sensible. This shaped the way I speak to people. On the other hand, living in a bottle with three other people was a deathtrap of rhetorical discussion. I found that most people grow up believing that there are certain pieces of culture that they are expected to conform to, and that it can vary widely.
The biggest problem was when things that were certainly not doctrine or commandments were treated as such. The problem was that they were discussed in a matter-of-fact way that tended to make others feel excluded. You do not need to be a Republican to be a Latter Day Saint. You do not need have to support gun rights or have a certain occupational path. Your baptism count does not affect your righteousness. The problem with Utah is that certain pockets of culture become attached to the church, and they become confused as doctrine. In the apartment, these become the expectations. It can cause great amounts of discomfort from those who do not share those views. Most of the time, challenging this sort of status quo immediately damages the newcomer's ethos.
This is the same effect the internet causes. Your points may be right. Your view may be fully qualified. But when issues are treated as enlightened vs. the fool, the bridge of communication is burned from both sides.
If there is untruth, fight it. If you are convinced you are correct, endeavor to convince others. But for the love of everything holy, do not start out by calling your opponents fools.
Rant over.