[GrandMoM]

the company directed employees to sign a "certificate of understanding."

Leave your politics and your religion at the door when you come to my place of business-....no problem, I expect as long as you do the same

[Eris]

The business owner can do as they please - it's their business.

If they want to make you wear green felt hats, you will wear a green felt hat or seek employment elsewhere.

You are not on equal footing with your employer.