The 1st Amendment (imo) is really what the whole American experiment hinges on, and there is a reason it is first. I absolutely believe people should be able to say whatever they want - as soon we get into sticky area of deciding what can be said and what can't, it's a never-ending can of worms. I believe the framers of the Constitution knew this, and also knew true freedom of speech brought risks with it, but that those risks were absolutely worth it, if we were to truly have a free society, and importantly - one in which the common man could speak truth to power.
But also contingent on all of the above is tolerance. We have to absolutely be willing to tolerate hearing things we may not agree with, without resorting to vile hatred and recrimination of our fellow citizens.
As the saying goes, "I may not agree with a single thing you say, but I will absolutely defend your right to say it."