Actually the First Amendment only applies when it’s the government telling you to pipe down - your employer has no such restriction.
While that is a very valid point, I do not look favorably upon a business that supports unAmerican activity, and punishes for proAmerican activity.
I will mention the First Amendment in my complaint.
It is a time honored thing, citizens speaking their minds regarding issues.
If it’s talking down the business or revealing secrets, I believe the business has every right to take action.
If it’s this type of thing done on a person’s own time, the business has no business sticking it’s nose in the tent.