Yes, we have free speech. But freedom requires responsibility. People with power have to realize that there are those who are so desperate, angry, scared, mentally unstable, etc etc etc, and those people will listen to these violent images and take them seriously and go and hurt others.
We live in an increasingly divided and troubled time. There are people on both sides who use these words carelessly, because it generates publicity, and with publicity comes followers and money. Unfortunately, when you spew things like using "second amendment remedies" to take care of the Democrats, or talk about reloading and taking aim at opponents, or have a map with targets on it, or talking about watering the tree of liberty with the blood of patriots and tyrants, people will take those things seriously and will try to find a way to follow through with the message.
We can still disagree with political ideologies in which we hold no belief. I will still speak out as a liberal against many conservative policies. But I will never say anything which would indicate that those beliefs need to be eliminated, with violent imagery. How horrible would it be if I said "Just like the Jews were eliminated in Nazi Germany, so too conservative policies need to be burned and gassed". I technically have the right to say that. The fact that I was able to use it as an example, proves that. However, it does nothing to add to the political discussions that we need to be having. We need to be discussing why things work, and why other things don't work. If something doesn't work, then we need to convince other people that it is time to move away from that idea. So instead of my previous statement, I could saying something like:
"I believe it is time that we move away from traditional views on this social aspect, because there are many people who do not hold to that view, and want us to progress forward".
That type of discussion is what we need to use our free speech for. It is the kind that builds our country up, instead of the bridge burning, walling building, red state/blue state, divisive screamfests that we currently engaged in.