You are still not seeing the difference. There is a specific law making it illegal for public employees to engage in a strike.
There is not a specific law making it illegal not to carry out your boss's policies.
There's a big difference there. Breaking a specific law means no arbitration - no union interference - no nuthin'. Firing someone who is not doing what you want them to do on the job is a whole different ballgame.
I wish it were otherwise - but we live in the real world, not the world I'd like it to be.
I guess that I am too used to being the boss. People who disobey or disregard my instructions are fired. Yes, that is the world that I'd like to see because the conduct of our foreign policy is more important than unions and the opinions of unelected petty bureaucrats.
You are not wrong. The system is.