Having worked as a licensed security guard(and a bodyguard) in the state of Texas I agree that when you work security there are a lot of work issues that come into play. If you work security long enough you will get thrown under the bus. It sucks, but it happens a lot.
I worked as a Spanish Interpreter in an Emergency Room in a hospital in a Dallas suburb for about 5 years. One day in the ER a guy got violent with a nurse and got him under control(I have a lot of martial arts training) so they created a special position for me in that ER as an Administrative Assistant. I worked Thursdays - Sundays 7pm - 7am. I saw a lot of stuff. During the course of employment there I attended Advanced EMT school, so that give me even more to do in the ER...
I got pretty well known in that ER(and the rest of the hospital) for my Spanish speaking abilities and being able to talk people down and physically restrain people without causing much damage.
There was a hot headed guy who was an XRay tech. He was good at taking XRays and CAT scans but not good at being told what to do. He bad mouthed one of the ER doctors which is a big no-no. He also showed up late quite a few times, so they decided to terminate him. They knew this guy respected me and knew better than to try to get physical me. So the director the XRay department asked if I'd walk him to the door when gave him his walking papers.
I was outside the office when they called him in to terminate him. He started threatening the XRay department director and the HR person there. He lunged at the director, I quickly stepped in and he backed off but kept making threats. I walked him out to his pick up truck and politely told him that he showed up on the property again the cops would be called and he'd be arrested. He told me several times that his beef wasn't with me and I told him I appreciated his respect. Staff in the Xray and ER departments were a little nervous for a few days but thankfully he never came back. About a month later he was shot and killed outside of a club in the Dallas/Fort Worth area. I wasn't surprised that happened, but I felt bad for his family.
Hot headed people are unpredictable. Sometimes they don't do stuff, sometimes they show back up ready to die. Always take threats seriously but know the environment.
If you're working with anti-gun people and you decide that carrying is more important than working there, then by all means, do what you feel you need to do. I have carried a concealed firearm around people that I knew would throw me under the bus if they knew I was carrying. I didn't do it often, but I did it.
One final point, if you are good at your job and almost everyone respects the job you do and how you treat people, you'll have a little bit more leeway in a work environment. But don't ever think you're irreplaceable because no one is. Learning to work with others, especially those who have opposing political and religious beliefs, is a skill that comes in very handy. It's a fine line between sacrificing your core values but also not making co-workers feel like you're inflexible and not open minded. Get good at what you do. Be consistent at being good at what you do. Be someone people can count on, especially those who didn't initially like you.