How have they not?
Many ways. Before citing the most recent example, let me reiterate that personal attacks on the President, his family, or members of his administration as well as on fellow Freepers is inexcusable under any circumstances. Of course, some egregious posts by whomever only deserve certain responses before the author is banned.
The most recent example of disrespect was another instance of the President treating us as children or idiots: In his latest immigration speech he responded to the real problem illegal aliens and their growing numbers, a very real and divisive problem affecting citizens of all parties and politics, by lecturing us on the virtues, the contributions and the historic importance to our present greatness of legal immigrants.
Our president is an intelligent man. Surely, if he did not write the words he certainly saw the banality and dishonesty in their use.
I won't even, at this point, mention the similar "vigilante" and "religion of peace" faux passes...