Most of the time, employment purges are not legal. If you are being pressured to resign, that is in itself a de facto admission that they know they can't fire you. Of course, none of this will prevent you from getting blackballed when applying for a new job, which is why it is wise to always use an untraceable pseudonym on the Internet and to avoid social media.Cheating at wrongful firings is mostly a matter of getting the leftists to do their own dirty work, which can be fairly enjoyable if you have the right sense of humor. Cheating at hiring and firing, though, is a different story.
To cheat at hiring, the easiest thing to do is have a comprehensive list of qualifications that no one can meet. This means that you can pick pretty much whoever you want for whatever reason you want because you can disqualify anyone at will. If you don't want to hire someone because he's an especially aspie atheist progressive, just say he doesn't meet your (impossible) qualifications. Thus, you have a legal justification for your personal decision. Just make sure that you have an official, approved story for rejecting an applicant and that you stick to it at all times.
Cheating at firing is a bit trickier, but it should be possible to offer an unwanted employee a promotion and raise and detail that the new job requires the execution of certain duties the employee is particularly unsuited for. After enough documented failures to perform, you can fire the employee with minimal chance of repercussion. Make sure to document everything, though, and never voice that the firing is related to anything but job performance.
Employment laws are mostly checklists. As long as every box is checked correctly, there shouldn't be much of an issue. As long as you can provide a reasonable professional explanation for your decisions, you can pretty much do whatever you want as far as hiring and firing goes. You just have to make sure that the right boxes are checked. These are the rules of the game; exploit them to your advantage.