One of the oldest rules of thumb in politics and satire is always to punch up, never punch down. If you are going to launch an attack or make someone the target of your mockery, pick someone higher up the chain of status and power, or at least on your level, not someone farther down. Beating up on the weak makes you look petty and fearful. It is what bullies do.
Naturally, therefore, Trump responded to the devastating criticism of him by the Muslim American mother and father whose soldier son was killed in Iraq by mocking the mother, saying she probably was not permitted by her husband to speak. He then compounded the error by saying that he had also sacrificed, by hiring thousands of workers and building big buildings!
What ought he to have done? Simple. He should have said, "Like all patriotic Americans, I honor the sacrifice of Mr. and Mrs. Khan. I hope as this campaign unfolds I can win their support." If Trump had a single sane, competent person in his entourage and was capable of taking good advice, he would be a much more formidable candidate. Thank God he does not.
And now he is complaining that the Clinton campaign has rigged the presidential debate schedule. I think there is at least a non-zero chance that he will back out of the debates. It is going to be a long three months.