Consider a woman, a citizen in a western democracy, Now consider that it is desirable to someone, for whatever reason, to have her behave in a particular way, to conform to some model, or submit to some reform. One way to accomplish this would be to use coercion, to invoke force or the prospect of undesirable consequences to influence her in the desired direction. Another alternative would be to use persuasion, appeal to reason, and try to convince her of the wisdom and benefit of the desired behavior, model or reform.
The first method is the resort to force. She will be made to conform regardless of her her own reason, values or choice. The second is a resort to rational discourse, to principles of analysis and evidence. Only the second of these is consistent with a respect for dignity; i.e. that a person is worthy, all else being equal, of living her life in accord with her own conscience.
Now image that the second method, the use of persuasion, is discouraged on grounds that the method of persuasion, i.e. free speech, might cause offense to someone. Thus we have in stark relief the malignancy at the heart of political correctness: that it is better to use force and the threat of personal consequences to bring about some policy or other, because to allow reasoned debate might offend subjective sensibilities. Rejection of political correctness is rejection of the notion that the benefits and individual dignity must be surrendered to protect the sensitive from disquieting opinions..